DE2328067A1 - METHOD OF USING A PHOTOGRAPHIC ELEMENT CONTAINING A PHYSICAL DEVELOPMENT ACTIVATOR - Google Patents

Description

Method of using a photographic element; which contains a physical development activator

The invention relates to "the field of photographic media, the Photography with physical development and various areas of application, such as photographic films, photographic paper, and printing plates. .- "■ ;.

The invention provides a photographic element that has a Carrier and on top of this a layer with seeds for a physical one Development or a photosensitive material capable of generating such nuclei on the support, which contains Layer contains a solvent-permeable binder, has a thickness below about 2 ρ and an activator for a physical Contains developer which accelerates physical development when the layer comes into contact with a physical developer causes and consists of a material that is preferably with the oxidized form of the reducing agent component of the physical developer reacts, as well as processes' for its use, in particular for the production of printing plates.

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Photochemical processes in which "physical developers" made of a solution of metal ions and a reducing agent used for these metal ions have been known for many years. In these procedures, a Image patterns formed from seeds for physical development by making a photographic element that is photosensitive Layer which, when irradiated, generates nuclei for physical development, is irradiated. That the photographic element containing the image pattern of seeds for physical development is then coated with a physical Developers contacted, being in those areas where the seeds for physical development the Catalyze selective deposition of metal, creating a metallic image.

Two different physical development processes have emerged in technology introduced. The first is transmission by diffusion, which is more accurate than a "physical evolution." can be referred to by solution ". In this process, a solvent is added to the developer in order to produce the silver halide dissolve in the non-irradiated parts of a silver halide printing medium so that the silver ions can be used for image formation appropriate physical development nuclei can be used. These germs can either be in their own layer on the same sheet as the Sxlberhalogenidschxcht or in a separate transfer sheet, as with the known Polaroid proceedings, be present. In a second physical development process that is also in technology introduced, the metal ion solution is applied to the irradiated photographic element in a separate bath, and a reducing agent bath is then applied to the element.

However, as far as the applicant is aware, there is no photographic one Process in which a "uniform" physical developer containing a solution of metal ions and a photographic Contains reducing agent for these metal ions, is used,

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known. A major reason for this is the lack of stability of such a physical developing solution. It is has already been attempted / to overcome the instability of these physical developers by adding ionic surfactants, Antifoggants and the like added (US Pat. No. 3,157,5o2 and 3 39o 998). From Jonker, et al. in Photographic Science and Engineering, Vol. 13, 1969, pp. 38-44 becomes a more preferred uniform physical developer described, which consists of a solution of ferrous ions, ferric ions, silver ions, a. Complexing agents such as citric acid and an ionic surfactant as a stabilizing agent for the physical Developer exists. By adjusting the concentrations of the various components of this physical developer are relatively fast development speeds with at the same time relatively good stability of the physical Developer has been achieved. Though, however, these preferred physical developer solutions are almost unlimited Durable when sealed from the atmosphere and not in use, they become oxidizing when they are oxidized Atmosphere, if air, is exposed and during its continued development according to concentration and activity unusable within hours or at best a few days .

In making printing plates using a single physical developer, two problems are particular Significance: (1) the stability of the developer and (2) the loss of fine detail in the parts of the printing plate with the. brightest pixels. At the manufacturing Of printing plates, it is especially important to use a physical developer that is a large amount of metal as compared to is able to deposit with conventional photographic materials such as films or paper. For example, with A usable printing plate about 0.1 to 2o g of metal per square meter of printing plate can be deposited in order to create the image the printing ink accepts and the abrasion in a printing press

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can be subjected. A preferred physical developer to deposit this amount of metal and also the type of metal that will be used for a long period of time is required is a unified physical Developer. When using such a physical developer, a printing plate can be produced by contact with the developer for no more than 2 or 3 minutes. To obtain such a physical developer, must but developers with such activity and concentration are used that the stability is less than desired is.

The problem of the loss of fine detail in the printing plate is "particularly severe when using this physical development process on aged photosensitive Printing plates "Halftone" printing plates are to be produced. These aged panels are those that are after their manufacture have been stored for some time. This is the case when using a photographic standard test (standard photographic test target) often impossible, the 5% -points still in an area with 65 line screen areas and even more difficult, to get them in a 13o line grid area. For high quality prints, a printing plate is used through this Loss completely unusable.

The present invention overcomes these problems of the conventional methods by firstly in the case the stability problem a unified physical developer with lower activity or development speed, which is of course more stable than a more active developer, can be used and secondly, printing plates with good Fine details and bright pixels, for example in the areas with the 5% purity of a 65 to 13o line grid (65-13o line screen) of an ordinary photographic test target can be produced. When the activator for the

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physical developer in excess of the amount the good 5% points in the 13o line grid area for generating good is required, it is possible to achieve such results in the 5% -point areas as they are for the production of high quality prints at a technical printing plate are required. In addition, the 5% -point areas generated in this way are also among the often considerable abrasion and wear conditions of the printing press sufficiently abrasion resistant.

In accordance with the invention, a physical developer activator is added to a photographic element comprised of a layer of physical development nuclei or a photosensitive material capable of generating such nuclei. An “activator for a physical developer” is to be understood as a material which increases the development rate of a uniform physical developer as defined above. A preferred activator for a physical developer is a material which will react with the oxidized form of the reducing agent in the physical developer to reduce its effective concentration. In particular, this material is an organic acid or a salt of an organic acid such as ammonium tartrate. This photographic element is used in a method which consists in that it forms an image of physical development nuclei and then, brings the medium with a uniform physical developer comprises a solution of metal ions and a reducing agent for that metal ions in contact. According to one embodiment of the invention, super stable unitary physical developers? d "h _o • physical developer of low activity, preferably when no activator" is used for. the. physical developer, such a development have © speed. "that after five minutes of contact with the physical escaped =" ler no useful image generated ^ is used, an image is

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to be considered useful for a printing process when on a standard lithographic press under ordinary conditions at least 1,000 prints can be obtained. A typical such press is using the Harris-Aurelia press of 22.6 kg (50 lb.) of white offset material with black printing ink (IPI black ink). For photographic film transparency, a useful image is one with an optical density of at least about 1. According to a further implementation, the Photographic element according to the invention used in a printing process in which in the photographic element a Image pattern is generated from physical development nuclei, the element is brought into contact with a uniform developer and the element provided with the image is then used as a printing plate. The printing plate obtained has improved Printing capacity with regard to the brightest pixels or fine detail areas of the printing plate. With a preferred one The photographic element of the invention has the physical development nuclei or photosensitive layer Material capable of producing such nuclei, less than about 2 microns thick, is preferably used in these processes Photosensitive materials are photoconductors such as silver halide, titanium dioxide, zinc oxide and tin oxide.

The "physical development activator" of the invention makes the selective metal deposition rate or optical density when a photographic element containing this activator is brought into contact with a uniform physical developer compared to the same photographic element which does not have this activator includes, elevated preferably the quantity and type of the activator in the element are selected such that the increase in speed äsr Keteilabseheiäung or optical density of at least 3g etws% and preferably -v-jsnigstensetwa te »©% _f based suf the Metaligewicht or optical density per sinus area per unit of time is _c Bei

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Process for producing transparent photographic films is expediently chosen as an indicator, the optical density while in processes for the production of printing plates as an indicator the amount of metal deposited is expediently selected. In this comparison of the rates of metal deposition - in any case a standard development time of five minutes applied using the same developer *

The activator according to the invention can be any material that the rate of metal deposition increases and is a different material than the physical development nuclei. A preferred activator according to the invention is a material, preferably with the oxidized form of the reducing agent. component of the physical developer reacts. This material is preferably a compound, preferably with the oxidized form of the reducing agent component of the physical Developer's complexes. Such a complexing agent is an organic acid or one in one Solvent soluble salt of an organic acid. Preferred organic acids are dicarboxylic acids such as maleic acid or malonic acid and hydroxycarboxylic acids such as salicylic acid, tartaric acid, lactic acid and citric acid. Particularly preferred are the hydroxycarboxylic acids and the soluble salts of these acids, such as the alkali and alkaline earth metal salts and the Ammonium salts of these acids. Particularly good results will be with the ammonium salts of citric acid, and tartaric acid Lactic acid achieved. Further suitable complexing agents are amino acids such as glycine, amines such as ethylenediamine, and / -Diketones, such as acetylacetone. Those activators are preferred, those with that used in the photosensitive layer or the physical development nuclei layer Binders are compatible, as well as a material that is not easily removed from this layer during the process will.

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Others suitable as activators for physical development Materials are those that increase the pH and thus the activity of the developer; Materials that are a source for Represent metal ions; and a reducing agent for the metal ions of the unified physical developer. In practice it has proven difficult to use a reducing agent, which has the storage stability required for normal use, and the addition of metal ions to the layer from physical development nuclei or photosensitive material often causes the problem of fogging.

Often it is possible to add the activator to the physical layer To introduce development nuclei or the light-sensitive material. However, it is also possible to use the activator in a to distribute its own layer above or below the layer of physical development nuclei or light-sensitive material. This is particularly desirable in those processes in which the layer consists of physical development nuclei or photosensitive material is less than about 2 microns thick.

In addition, as is common in the photographic art, the activator must usually be in a solvent-permeable binder to be present. This binder serves the purpose of a memory for the activator, which by increasing the layer thickness can be increased, and also acts as the activator during the time of contact with the photographic element dissolved out of the layer with the physical developer.

The term "unitary physical developer" is intended to the "two-step physical developers" and those mentioned above exclude "physical solvent developers" where the stability of the developer is not an issue. The uniform physical developer is a solution of metal ions and a reducing agent for these metal ions

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and is capable of selectively metal on a photographic medium, that is a layer of physical developer nuclei and preferably by irradiation and further if necessary Processing a photosensitive layer is formed to be deposited. The physical developer according to the invention does not require the application of an external electric charge as in electrolytic development.

The physical developers preferably contain according to Invention of surfactants as stabilizers to prevent decomposition to prevent. The preferred surfactants are those from US Pat. No. 3,157,502 known ionic surfactants.

The best results are with the physical developers obtained at pH values below 7, i.e. in acidic media, usually at a pH of about 1.2 to 1.7. Lower pH levels are too high because of the possible impairment of surfactants which are sensitive to low pH levels avoid.

In the physical developers, the reducible metal ion is usually an ion of a metal at least as noble such as copper, for example silver, copper, gold, platinum, palladium and the like. However, other metal ions, how ions of nickel and tin are used when appropriate reducing agents are used. Reducing agent for copper, silver and other precious metal ions are easy to determine and adequately described in the literature.

A particularly effective unitary physical developer consists of silver ions, as a reducing agent ferrous ions, ferric ions and preferably a material that preferably a complex with the ferric ions of the developer forms, for example an organic acid such as citric acid.

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One of the main advantages of using the physical development activator in the photographic element according to FIG of the invention is that a low activity physical developer can be used. This developer low activity is a uniform physical developer that is excellent because of its low activity Has stability. For example, an ordinary unitary physical developer becomes impoverished in his steady state Use for developing printing plates with an excess of exposed halide emulsion within a few Hours so complete that it has to be completely replaced with fresh developer. That is the case even if a developer replenishment system is used which removes a portion of the used developer while the developer is in use replaced by fresh developer. By using the less active developers according to the invention, it will now possible to keep the developer stable for a few hours if it is used steadily, and still a sufficient one To achieve metal deposition so that a useful printing plate or, in the case of photographic film, an optical Density of at least about 1 is obtained. A preferred inactive unitary physical developer for printing plates is a developer that, on contact with a plate, has an exposed silver halide layer without contains the activator, causes so little metal deposition for a time up to "about five minutes that it is not possible to use an image which can be brewed for printing, i.e. an image capable of making at least 1,000 prints on an ordinary lithographic printing press under ordinary conditions are to be generated. A preferred inactive unitary physical developer for. is a photographic film a developer which, on contact with a carrier, has a coating of exposed titanium dioxide in a binder layer unable to produce an optical density of at least about 1 for up to about five minutes.

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This little active physical developer is preferably a developer that has a development speed of less

2
less than about 2oo mg metal / m / min. in developing a photographic element consisting essentially of a lantern silver image formed by irradiating one of the silver halide layers of Example 1, but without an activator for the physical developer. According to the invention, it is even possible / physical developers with such a low activity that the development rate on contact with one formed by irradiating a photographic element which contains silver halide but does not contain an activator for physical development is practically zero. The rate of metal deposition in this type of physical development is controlled by factors well known in the art, concentration of metal ions, pH, temperature, and the like. A preferred low active physical developer is a developer with a ΔE below about 100 mV. For the manufacture, development of printing plates is a developer with a E zwisehen about 6o and about 1oo mV particularly preferred because particularly good prints are obtained. In the preferred physical developer system consisting of a solution of silver ions, ferric ions, ferric ions and a complexing agent which preferably forms complexes with the ferric ions, the ΔΕ is adjusted by varying the concentration ratios of these various components.

For the purpose of defining the δE, the unitary physical developer solution can be viewed as consisting of two parts, namely (1) a solution of a reducible metal ion (Me ⁺² ), and (2) a solution containing all of the remaining components of the physical developer. The reversible potential of the metal, Me, immersed in a solution of part (1), against a reference electrode (e.g. a saturated calomel electrode) can be called E.

Me ^{+ Z} / Me

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The potential of one immersed in a solution from part (2) inert metal electrode "(for example Pt) against the same reference electrode can be called E, _. The value of ^ E gives then to:

^ E = E - E ^r Me ⁺² / Me (2)

A preferred inactive physical developer is a developer whose use slows the speed of the Metal deposition is less than when using a reference developer of the following composition:

o, o5o mol / l ferrous sulfate o, oo5 mol / l ferric nitrate o, 14 mol / l citric acid ο, οοδ mol / l silver nitrate

o, o2 wt .-% ionic surfactant (Armac 12Ώ) Λ as Stabilio, o1 wt .-% nonionic surfactant (sator for the (Lissapol N) J developer

The seeds for physical development preferably consist of a metal such as silver, gold, mercury, platinum, Palladium or the like. In silver halide photography, the latent silver image is formed in the silver halide grain in of the emulsion upon exposure, and physical development is applied to visualize the latent image. When irradiating a photosensitive material such as a metal oxide such as titanium dioxide, zinc oxide or tin oxide

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and is brought into contact with a solution of a reducible metal ion, a latent metal image is formed which is visible or can be invisible and enhanced by a unitary physical developer, or it is possible apply the unified physical developer directly without first applying the metal ion bath.

The picture from physical development nuclei can be:

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(1) The image formed by irradiation, such as the latent silver image in silver halide emulsions or the reversible latent image on a reversibly activatable Photoconductors such as titanium dioxide;

(2) the irreversible image formed when an irradiated photoconductor-bearing medium is exposed to a sensitizing metal ion, for example a silver ion solution, brings into contact, resulting in an invisible can lead to an irreversible image or a visible metal image;

(3) the ferrous ion latent image obtained by irradiating a medium sensitized with ferric salt, which is then treated with silicon ion solution is sensitized to form a silver image; or

(4) a conductive image or seed image produced by printing or writing in accordance with FR-PS 7 o33 1o6? by physically placing a metal image on the substrate; by diffusion transfer of metal ions according to US Pat. No. 3,300. 3o6; by means of an image-wise exposed photopolymer layer over a seed layer, for example in accordance with US Pat. No. 3,615,446 and US Patent Application SN 697 948, dated January 15, 1968? or the seed image formed by irradiating a pre-fogged (prefogged) photosensitive material such as lead iodide or As ^ S ₃ , as described in Malinowski, "Photographic Science and Engineering," Vol. 15, No. 3, May June, described.

A preferred photosensitive material is a photoconductor, like silver halide, or a photoconductor that activates reversibly when exposed to activating radiation and is able to cause a chemical reaction in the irradiated areas. The photoconductor is preferably in finely dispersed form and is preferably incorporated in a binder permeable to solvent water and

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in the form of a very thin, removable layer on top of that Carrier, in particular deposited on a carrier with a roughened surface, in such a way that at least part of the photoconductor is contained impregnated in the roughened part of the carrier. For example, a photoconductor such as silver chloride, deposited in a binder solution of relatively low viscosity and the mixture thus obtained then applied as a coating to the roughened carrier will. The coating mass can be left to dry. Such a carrier with a coating of photoconductor in The binder preferably has a very thin coating that is permeable to solvents and therefore a rapid process -working allowed in the preferred developer system.

A physically developable image can be created by physical development or germ nuclei are applied to the metallic support. It can do that take place that one describes the metallic carrier with, for example, a graphite pencil or by one Seed core layer, preferably in a binder and with a layer that can be made opaque, coated, applied and then irradiated to make this layer impermeable in the irradiated areas. The seed kernels can be any material that catalyzes the deposition of metal from the physical developer. Many such materials are known. Examples are metal sulfide, finely divided metal particles, graphite and the like.

The preferred photosensitive media are those containing silver halide as a photosensitive material. Such photosensitive media are known and described in detail in the literature. Particularly preferred

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Silver halide containing media are those that have a low silver halide content in the photosensitive Layer, and especially those that have halogen ions in a stoichiometric excess over the amount of silver ions contained in the photosensitive layer.

The preferred media according to the invention have one layer of photosensitive material less than about 2 microns thick, and preferably less than about 300 microns thick. Most preferred are Layer thicknesses below about 100 μm. The silver content of such layers th is usually around 0.05 g / m and can go down to

2
ο, οΊ g / m in the most preferred layer thicknesses.

The so-called thin photosensitive layer with low silver content is a preferred embodiment of the invention, especially in connection with metal supports for the production of printing plates, electrical components and As the silver halide, a silver halide is used as it is commonly used in photography will. It is made in a conventional manner, i.e. by reacting an aqueous system of soluble silver salt such as silver nitrate or sulfate and a soluble alkali halide such as sodium chloride, sodium bromide or sodium iodide or the corresponding Potassium salts. The formation of the silver halide particles can be controlled so that any desired Particle size in a range from down to 3o to

ο.

50 Å up to conventional particle size can be obtained. Preferred practices are those that are very educational favor small particles, usually below 0.5 u. Such fine particles are conveniently obtained by High solids systems, preferably about 5% total solids (including the _ weight of, -silver halide and binders) and the alkali halide solution rapidly with the silver salt solution, usually

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at about room temperature.

That for the activator for physical development and / or the layer of physical development nuclei or The binders used in the photosensitive material can be any of the solvent-permeable materials, as they are usually used for the production of silver halide or Photoconductor emulsions used for physical development will be. Preferably, the binder is sufficiently wettable by aqueous solutions to allow rapid development to allow the exposed layer. Preferred binders are the usual gelatin used for silver halide films is used, polyvinyl alcohol, polyacrylamide, polyvinylpyrrolidone, poly (methyl vinyl ether) -inalein anhydride, Ethylene / maleic anhydride copolymers, polyacrylates, including Polyacrylic acids, casein and the like. The use of polyvinyl alcohol is particularly preferred when very small silver halide particles are desirable because the binder is likely to ripen, i.e., grow the silver halide particles when standing, counteracts.

In addition, other materials can make up the layer of binder and physical development nuclei or photosensitive. Material can be added to this layer cause special effects during or after irradiation. For example, sensitizing dyes, Thiourea, toner, mercury salts or the like can be added to the known ones caused by them to achieve photographic effects. For example, thiourea can help to prevent the formation of blacks photographic images can be added and the black sensitizing dyes can be added to. the spectral response of the photosensitive layer to change the irradiation.

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The photosensitive material can be any of the materials known from the literature, for example US Pat. No. 3,380,823 or US Pat. No. 3,623,865. In general, the preferred photoconductors are silver halides or compounds of a metal with a non-metallic element from Group VI of the Periodic Table. These photoconductors are preferably metal oxides or sulfides, such as titanium dioxide, zinc oxide, zinc sulfide, cadmium sulfide _A, cerium oxide and others. Preferred oxides are titanium dioxide, zinc oxide, tin oxide and mixtures thereof.

The seeds for physical development or photosensitivity Liche material and the physical development activator in the selected binder are made according to any known one Technique, for example with the help of rollers, applied to the carrier in the desired thickness. After drying the photographic medium is ready to use. If desired, an overcoat can be applied to the photographic Protect emulsion. The emulsion can of course also contain substances as they are commonly used in connection with the particular light-sensitive material, for example Dye sensitizers, sensitizing metal salts, such as silver and copper salts, photographic reducing agents and other materials commonly used in photographic emulsions.

The exposure is as normal for the particular photosensitive material. Also the processing of the exposed Medium is carried out as normal. .

As a carrier for the medium according to the invention, anyone can usually used carrier, "such as paper, plastic and metal can be used. For example, for transparent

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te films cellulose acetate and polyethylene terephthalate are used are printed while for the manufacture of printing plates and printed electrical components, for example Circuits, capacitors and the like, and for name plates and metallic decorative plates, metals such as aluminum and Iron as well as alloys thereof can be used. the Preferred supports for making printing plates suitable for a large number of prints are granular metal supports. Particularly good results are achieved with anodized aluminum supports.

Any suitable metallic or substantially metallic stiffening material can be used for the preferred metallic supports of sufficient strength and durability to be used as a reproduction support. The carrier can be in any form, for example as Foil, tape, roller, etc. are present. A foil can be made of any suitable metal or alloy, for example the hydrophilic metals such as chromium, nickel, lead, stainless steel, magnesium or aluminum, or the oleophilic metals, such as copper or zinc. Aluminum is preferred because it has very desirable physical and chemical properties has and besides-is cheap. Under "aluminum" also alloys of aluminum, such as aluminum, which contains small amounts of manganese, copper or magnesium, understood will. Preferably the aluminum support has a porous anodized surface. The anodized surface can through Heating to be sealed. The unsealed surface is however, preferred because it gives better adhesion between the metal image and the aluminum support. For printing plates, many of the prints of which are to be made, an alloy such as type 1 100 aluminum is used, which is durable against cracking, 'and has sufficient strength.

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The preferred metal support can be of any suitable thickness. A thickness of from 0.015 to 0.15 is preferred for printing plates o, o58 era (.006 to .o25 inches) and especially for cross-country printing plates a thickness of o, o3o to o, o38 cm (0.0I2 to o.o15 inches).

The carrier and image metal can be chosen so that there are good differences between oleophilic and hydrophilic areas for use in lithographic processes. Even can perform this procedure using .special treatments to produce plates which can be used in the so-called driographic manner as described in US Pat. No. 3,511,178.

Granular metal supports are preferred according to the invention used. These carriers are able to form a bond with the metal image formed during physical development, see above that a plate is obtained which can be used as a printing plate and preferably as a long-running printing plate, and the when testing with the optical and surface roughness meter (Optical Surface Roughness Meter (OSRM) with a curve a peak height A between about 0.25 and about 0.9o at a point B between about 0.35 and about 0.80 and a psi value C has between about 0.4 and about 1p. Such a grain can be made by physical grain, for example by brush, stenkömung, spherical grain, grain size with the sandblasting blower or by chemical graining, for example by etching with acid or alkali. A chemical grain can for example by electrochemical treatment in an acid such as hydrochloric acid, nitric acid or a combination of nitric acid and acetic acid.

According to a preferred embodiment, cross-country printing plates are grounded with metal support »*, whose barrel length the bimetallic plates are comparable, generated (run lengths over 15o 000

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a common lithographic printing press among common ones Conditions). For the production of line copies (line copy) plates are used in which the grain of the metallic carrier, preferably aluminum carrier, shows a curve when examined with the QSRM device with a peak height A between about 0.5o and about 0.55 with a peak position B between about o.6o and about ο.75 with a psi value of C between about 0.65 and about 0.9o. For the creation of semitones the curve has a peak height A between about o.75 and about o.85 with a peak position B between about o.7o and about o.75 and a psi value C between about o.75 and about o.9o.

Under-a- "cross-country printing plate" is one with a Imaged printing plate is understood to be taking on a conventional lithographic offset printing press ordinary conditions, for example on a Harris Cottrell M-looo press manufactured by the Colonial Press Inc., Clinton, Massachusetts, V. St. A., which measures 24 3/4 "by 36 1/2" (62.9 cm by 92.7 cm) 4-unit offset printing press that works with a thermosetting web is (perfecting heat set weg offset press), at an operating speed of 26,000 prints per hour on white flat printing paper (22.7 kg, 50 lb.) using black printing ink (IPI), non-compressible Dayco wipes and Imperial humidifying solution at least about 1,000,000 good quality prints, and preferably at least about 150,000 prints ■ can produce without causing deterioration of the image or separation of the image from the printing plate leads to a loss of quality.

If a plate provided with a picture is used as a printing plate is used in accordance with the invention, it produces

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at least about 5,000 prints on a conventional offset lithographic printing press below ordinary Conditions. Typical of such a press is the Harris Aurelia press.

An optical surface roughness is used to measure the grain size of the metal supports used according to the invention smesser (optical surface roughness meter (OSRM), as described in patent application P 22 41 474 (BE-PS 787 828) is described / used.

As described in the aforementioned patent application P 22 41 474, The OSRM generates four curves that show the grain of the Mark the metal support. The curves are more easily identified by the following four parameters:

(a) Peak height A (vertical axis with one from zero to

1 , σ scale) of the highest of the four directional curves obtained on each surface,

(b) the peak position B (horizontal axis on a zero to 1 _r o reaching "scale) of the highest this direction curves obtained on each surface,

(c) the psi value C, which is used as a measure of the fine structure of the surface is used and is defined as follows is: -

(1) Peak height A and peak position B are determined

(2) the 'height of the OSRM curve for the highest of the four Curves are determined at position o, 9o on the horizontal axis, and

(3) the psi value is the ratio of the value obtained in (2) and the peak height A, and

(d) the asymmetry - the asymmetry results numerically as the value of the difference between the peak height A and the height of the lowest curve at the stiff ^ B

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on the horizontal axis.

The thickness of the layer of physical development nuclei or of the photosensitive material capable of generating such nuclei, the insulating layer, if any, depends on the species the photosensitive material, the type of the binder, if present, the amount of activating radiation and the like Pactors. However, so that a quickly processable image-generating

'The medium is obtained is the layer of physical Development nuclei or photosensitive material relatively thin, i.e. preferably less than about 2µ and more preferably less than about 1µ thick. The thickness of these layers however it can vary. For example, if a metal support is used, the photosensitive coating or the coating can be made from

- physical development nuclei with the exception of the parts that are sunk into the roughened surface are scraped off. The thickness of the pull can vary depending on the desired effects vary. Most preferred, however, is a carrier in which this coating has a thickness of less than 1 μ, so that, coherent metal images, which adhere firmly to the carrier and can be processed quickly, are obtained.

According to a preferred embodiment, a transfer plate Made with internal diffusion by adding a layer of physical development nuclei, such as Carey Lee silver applies to a carrier so that the dry thickness of the Layer is about 2 μ. A layer of silver halide, which is exposed as in US Pat. No. 3,615,37, is applied to this layer and can be developed, but the activator according to the invention is additionally introduced. ¥ or preferably the image generated by physical solution development is then stabilized with the help of the uniform physical developer according to the invention instead of with the Electroplating baths of U.S. Patent 3,615 ^ 37 reinforced.

When used, the ratio of the amount of binder to the amount of physical development nuclei or light-

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sensitive material vary widely. Preferably the weight ratio of seeds or photosensitive Material to binder between 1 to 6 and 6 to 1 and especially between 1 to 1 and 1 to 3

As radiation sources for generating the latent image, according to the invention, all usually for the selected light " Sensitive material used radiation sources are used. That means actinic light, Hontgen rays or Gamma rays are used when photoconductors are used .. Instead of the usual forms of electromagnetic radiation you can use electron beams or other particulate beams can also be used to produce an image. All of these activators are referred to as "activating radiation".

It may also be desirable, in the preferred silver halide emulsion, contains the halogen ions in excess and in the one stabilized physical developer is used for development, a sulfur compound is used as a development initiator bring in. A preferred compound is thiuram, such as tetramethylthiuram disulfide. The initiator determines the quality of the metal deposition, which is reflected in the physical development an exposed silver halide plate is improved.

According to a further preferred embodiment of the invention, it has turned out to be in the production of metallic printing plates It has been found useful to add a layer of ionic surfactants to the photographic element as described in US Pat. No. 3,157,502, e.g. Armac 12D (ionic surfactant) and Synthrapol N (non-ionic surfactant). The surfants can including those containing the physical development activator Layer or the layer of photosensitive material or physical development nuclei are added. It was found, that the presence of the ionic surfactant in the

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photographic element metal images of improved printability results, so that both the printing quality and the usability of the printing plate can be improved considerably, especially if the little active uniform physical developer for the production of the metal image on the Plate to be used. ·

example 1

A 5 # solution of polyvinyl alcohol is prepared by slowly adding powdered polyvinyl alcohol to room temperature distilled water with rapid stirring. The temperature is slowly increased to 95 ^° C. with continued rapid stirring and held at this value for about 1/2 hour.

The following solutions are made using the thus obtained 5 # polyvinyl alcohol solution produced (figures in percent and dimensionless numbers refer to the weight):

Solution a . Solution b

Distilled H ₂ O. 326.0 Distilled H ₂ O 456.0 10 ^ aq. NaCl 92.7 10 # aqueous AgNO ₃ 244.5 5 ^ aq polyvinyl alcohol 414.0

(Solution B is only prepared immediately before the described use, i.e. it is freshly prepared before being used with others Solutions is mixed.) Solution A becomes about 4 at room temperature with a high speed mixer Minutes stirred. Solution B is then added and the mixture is stirred for a further 5 minutes. Then the mixture is through Filtered a 5p. bag to make an emulsion with the following Properties is obtained:

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AT

Emulsion constants;

Silver chloride to polyvinyl alcohol 1: 1 ( parts by weight) ίθ% excess of chloride 3 * 5 # total solids 13.5 g silver chloride / liter

pH = 5.2 to 5 * 4 '

Viscosity = 4 to 5 cp

- 59 mg ammonium citrate per gram of silver chloride 1 mg T-M

The emulsion is then applied as a coating to grained aluminum substrates, either by air knife or with rollers or other means of producing coatings. Good results are achieved with hard rubber rollers. With a suitable setting can easily be a coating with a weight of 0.05 g / m can be obtained. The carriers have a grain produced electrochemically or by means of brushes.

The grained aluminum beams are aluminum beams with a thickness of about 0.030 cm (0.012 inch) and an electrochemically generated grit and are anodized so that the OSRM has the following grit defined: peak height A - 0.93i peak position B - 0.73; psi value C - 0.88 and asymmetry 0.03.

A plate coated in this way is then with a top coat (wet coat thickness 0.075 mm, 3 mils) from a solution of the following composition:

t-butylamine tartrate - $ 20

Polyvinyl alcohol Gelvatol 40-20) -

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.Λ

After drying, the plates are covered with a 250 W quartz / iodine lamp 30 seconds image-wise from a distance of 76 cm (30 inches) exposed. The plates are developed with a zero potential developer of the following composition:

Fe (ClO ^) ₂ - .0.1 m Fe (NO-,), ^v - 0.06 m AgNO, - 0.09 m

Dark, black, adhesive images that accept printing ink are obtained. These plates can be used in a printing press to make copies.

Example 2

A plate is coated with a silver halide emulsion coated as in Example 1 and then with a top coat (Wet thickness of coating 0.075 mm, 3 mils) from a solution of the following Composition provided:

Ammonium tartrate - £ 4

Polyvinyl alcohol (Gelvatol 40-20) - 15 #

After drying, the plates are covered with a 250 W quartz / iodine lamp Exposed for 30 seconds from a distance of 76 cm (30 inches). Then the plates are placed in a 53 mV developer for 120 seconds the following composition developed?

Pe (NH ₄ ) ₂ (S0 ₄ ) ₂ - 0.105 m

Pe (NO ₃ ), - 0.095 m

Tartaric acid - 0.053 m

AgNO ₃ '- 0.068 m

Ionic surfact ant ''
(Armac 12D) - O ₁ OIlSi

Non-ionic

Surfactant

(Synthropol N) 0

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Dark, black, adhesive images are obtained. These pictures accept printing ink and are used on a printing press to make copies.

Examples 3 and 4

Examples 1 and 2 are repeated with the difference that in the top coat the complexing agent is omitted. After exposure and development according to the process in Examples 1 and 2, no images are obtained.

Examples 5-11

Examples 5 and 6 illustrate a uniform zero potential stabilized physical developer. example Figure 5 shows that no imaging occurs when the complexing agent ammonium tartrate is omitted from the emulsion.

Examples 7 and 8 illustrate a physical developer of low ΔΕ. Again, Example 8 shows that in the absence of the complexing agent in the emulsion Development takes place. . .

Example 9 illustrates the use of a developer of low Δ E with a paper carrier.

Examples OK and 11 show the same kind of results as that Examples 7 and 8. They also show that with this system good Results can be obtained with relatively short development times (i.e. 5 seconds).

Emulsions of the compositions shown in Table 1 are exposed to activating radiation and developed using the stabilized uniform physical developers of Table 2 according to the procedures of Table 3, the results shown in Table being obtained. ^/

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3 0 9850/1007

Tabel

Composition of aqueous emulsions for the production of coatings * on a film or paper

Composition of the emulsion, wt -.%

Example no, component titanium dioxide ammonium tartrate polyvinyl alcohol (Elvanol 71-30> polyvinyl alcohol Gelvatol 40-20 polyvinylpyrrolidone (PVP K-90) polyacrylamide (Cyanomer A-370) dispersant (Triton X-IOO) dispersant (Ekaline G-80)

5 6th 7th 8th 9 10 ■ 0.008 11 8.7 8.7 8.0 8.0 ^{ 8.0 3.9 3.9 4.4 4.0 4.0 3.9 2.0 2.0 2.0 1.0 1.0 2.0 2.0 2.0 1.0 1.0 0.8 0.8 0.8 0.2 0.2 1.3 1.3 0.03 0.03 0.01 0.01 0.01 0.0 0.009 0.009

Insulating support triacetate Boryta paper, single weight

The emulsions J ^1, 8 and 9 were applied by machine. The coatings of Emulsions 5, 6, 10 and 11 were applied by hand with a Gardner machine. In addition, 5 and 6 were given a top coat of a 30% solution of Gelvatol 40-20.

NJ CO CD CD

Table 2

Composition and Δ Ε of the physical developer

Number Fe (C10h) _P Fe (NHh) ₀ (SO ₂ I) ₀ Pe (NO,) - ■ Wine- Silver- ionic non-ionic

Mol / l * * Mol / l * * * * Mol / K * acid nitrate surfactant surfactant mV

Mol / l Mol / l (Armac 12D) (Synthrapol N)
■ wt .- ^ #

0.300

0.030

0.018

IV)

vo

0, 105 ö, 105 0, 053 O, 068 0, 011 ° * 011 46 0, 109 0, 072 0, 054 0, 035 ■ 0, 011 • 0, 011 56? §

Tabel

Examples of processing and sensitometric results using the emulsions of Table 1 and the developer of Table 2

Example ⁰ Awareness Development

(AgNO,),
Minor-* Time,
Sec. 5 0.5 10 6th 0.5 10 7th 0.05 45 8th 0.05 - 15 9 0.1 5 10 0.1 15th 11 0.1 15th

Ge s c hw ind i gke. it

Developer time at 0.2 sec.

1 2 2

60 0.0096 60 e 60 0.020 60 e 60 0.036 Ul 0.0087 60 e

gamma Maximum
optical
density Optical
density
Base and
veil 1.1 1.56 ° 0.16 ° e 0.14 ° 0.14 ° 2.7 2.6 ° 0, -17 ° e 0.17 ° 0.11 ° 1.15 I, l8 ^d 0.08 ^d 2.24 2.02 ° 0.21 ° e 0.14 ° 0.11 °

^a All coatings were on an EG&G. Sensitometer 10 "* ^ seconds exposes speed = l / log energy (meter-candle-sec.) At 0.2 above base and veil (above

base and fog)

^c Transmission Optical density for transmission

Optical density on reflection
^e values too small to be determined

CO NJ OO

Example 12 .

Two emulsions were made as follows:

A first emulsion is made by mixing 4 g of gelatin in
40 ml H ₂ O (40 ⁰ C) are dissolved. This ^ solution is slow
A dispersion of O, Ig argyrol (a commercial product for the production of colloidal silver) was added with stirring.
Then 50 ml of H ₂ O,. containing 4 g of ammonium tartrate, added.

A second emulsion is after. same procedure as that
first produced, with the difference, however, that the ammonium tartrate is omitted. ".

The above emulsions were coated on an isolating triacetate base, allowed to dry and then developed for 60 seconds in a uniform physical developer of 56 mV having a composition corresponding to No. 3 of Examples 5-11. Silver separated from the emulsion containing the ammonium tartrate, but not from the other emulsion. Similar results
are achieved when a negative image is first created over the layer of physical development nuclei, for example by adding a silver halide layer to the silver nucleation layer
coats, dries and developed into a negative image. When developing with the uniform physical developer, a positive image will form in the seed layer if a physical development activator such as ammonium tartrate, ammonium acetate or ammonium citrate is present.

Examples 13 and 14

Examples 1 and 3 are repeated with the difference that
a 1.5 ^ solution of a hydroxyethyl cellulose (Gellosize QP-4400) is added to the developer with zero potential in sufficient quantity to make the developer highly viscous. There will be similar

309850/1007

Results obtained as in Examples 1 and 3 * i.e. in the presence of the activator, an image is formed on the copy medium during development; However, if this activator is not present, there will be no. Image generated.

Example 15

A copying medium that contains titanium dioxide and ammonium tartrate in one Polyvinyl alcohol binder on an insulating triacetate coating-contains, will be 10 ~ ^ seconds on an E.G. & G. Sensitometer exposed, with an aqueous solution of 0.1m silver nitrate Brought into contact for 15 seconds and then contacted with a physical mercury developer of the following composition brings:

0.105 m Fe (NH ₄ ) ₂ (S0 ₄ ) ₂

0.095 m Fe (NO,),

0.053 m tartaric acid

0.011 % ionic surfactant (Armac 12D)

0.011 % non-ionic surfactant (Synthrapol N)

0.05 m

In the exposed parts of the copy medium a dense

black image of D " _e " 2.9 and gamma 3 * 0 generated.

Max

If the above example is repeated except that the ammonium tartrate is omitted from the copy medium, will does not form an image on contact with the physical mercury developer for the same time as before.

Examples 16-18

An anodized aluminum carrier, provided with grains and anodized as in Example 1, is coated with a coating by means of rollers from an emulsion of the following composition:

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1 = 1.35g AgCl + 10 $ excess Cl

a) 0.6 $ NaCl

b) 1.6 $ AgNO

c) - 1,3Ji Lemol I6-98.

d) $ 0.014 ammonium citrate *

e) $ 0.001 thiuram

After the emulsion has dried, the layer has a thickness of about ΐ / 3μ. The coated aluminum plate is then coated with a top layer of ammonium tartrate / Si using a Gardner coating device
to be added:

Ammonium tartrate / surfactant binder of the following compositions

a) 2 $ gelatin 2166

b) 4 $ ammonium tartrate

- e) 0.08 $ ionic surfactant diamine 4) 0.08 $ acetic acid
$ 0.08 non-ionic surfactant (Synthrapol N)

This topcoat has a wet thickness of about 0.075 mm (5 mils).

After the coating has dried, the plate is covered with a for 20 seconds Quartz / iodine lamp exposed at a distance of 76 cm (30 inches). The exposed plate is stabilized for 3 minutes in a uniform physical developer of 73 mV of the following composition developed: -

0.103 m Pe (NH ₁ ^) ₂ (SO ₄ ) ₂ 0.068 m Pe (NO ₃ ) ₃ 0.052 m tartaric acid 0.083 m AgNO ₃ 0.010 $ ionic surfactant (Armac 12D)

0.010 ^ non-ionic surfactant (Synthrapol N)

An excellent silver image is created, which is then combined with a Printing varnish containing a mercaptan and an oleophilic resin and

3098 507 1007

selectively adheres to the silver image areas and the plate is ready for use for a printing press, is rubbed off. The printing plate thus produced is then placed on an ordinary offset lithographic printing press and used to make 100,000 copies.

The above example is repeated with the difference that the ammonium tartrate is omitted from the top layer. To with the same exposure and development as described above, no image is produced.

The procedure of Example 16 is repeated with the difference that ionic and non-ionic surfactant from.the top layer be omitted. A visible image is created by exposure and development as described above. This picture is suitable siöh not for a printing plate and results if it like

treated on top with a lithographic lacquer and / a printer -press is applied, a completely unacceptable pressure.

Examples 19 to 26

A 5 # solution of polyvinyl alcohol is prepared "by slowly adding powdered polyvinyl alcohol with rapid stirring. added to distilled water at room temperature. The temperature is slowly increased to 95 ^° C. while continuing to stir rapidly, and the mixture is ^{kept at 95 °} C. for about 1/2 hour.

The following solutions are made using the 5 ^ strength polyvinyl alcohol solution manufactured (percentages and dimensionless numbers relate to weight) ϊ

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2237
Solution a - 414.0 3Γ
Solution b H ₂ O 2328067 100 NaCl - 92.7
Solution C Distilled
105Ü- AgNO ₃
Solution D 2.06 - 456.0
- 244.5 5% polyvinyl alcohol
(Lemol 16-98) 1% thiuram -

Solutions A, B and C are ^{heated to 30 °} C. and solutions B and C are mixed with one another. The mixture of B and "C is then stirred rapidly in a high speed mixer and solution A is slowly added over 2 minutes. The mixture of A, B and C is stirred for 3 minutes. Solution D is added and the mixture is stirred for a further 5 minutes.

The mixture is then filtered through a 5 | J bag, whereby the Emulsion No. 1 is obtained with the following properties:

Emulsion constants:

1: 1 (parts by weight) silver chloride to polyvinyl alcohol 10 # excess of chloride
$ 4.5 total solids
17.1 g silver chloride / l
. 1 mg thiuram
Viscosity - 6 cp pH - 5.7 ^; .

S * I

A second emulsion, Emulsion No. 2, is prepared by mixing the following solutions (parts by weight) together :

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3 0 9850/1007

Solution A - Solution B

Distilled water - 384.0 Distilled water - 384.0

$ 10 NaCl - 61.8. $ 10 AgNO, - 163.0

5 $ polyvinyl alcohol 5 $ polyvinyl alcohol

- (Lemol 16-98) -412.0 (Lemol I6-98) -412.0

Solution C

$ 1 thiuram - 1.40

(Solution B is only prepared immediately before the described use, i.e. it is freshly prepared before it is mixed with the other solutions.) Solution B is at room temperature stirred with a high speed mixer. Solution A becomes rapidly with rapid stirring the solution B added. The mixture is stirred for an additional 3 minutes, after which time solution C is added. The mixture is left for an additional 5 minutes stirred, and the mixture of A, B and C is filtered through a 5 | J. bag, producing an emulsion with the following properties is obtained

Emulsion constants:

1: 3 (parts by weight) silver chloride to polyvinyl alcohol 10 $ excess chlorine ions 3.5 $ total solids
7.6 g silver chloride / l
■ 1 mg thiuram

The emulsions No. 1 and No. 2 are divided into 300 g portions, and the following salts are added to each portion:

A. Sodium ethylenediaminetetraacetic acid

B. ammonium citrate

C. Ammonium tartrate

The salts are added in concentrations of 0.166 g and 1.33 g

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3098 50/1007

etch them by first soaking them in 10 cubic centimeters of distilled water dissolves. Emulsions 1 and 2, which did not contain any of the above salts A, B or C, formed the basis of two comparative emulsions.

The emulsions were then by means of air knives, rollers or other coating agents applied to grained aluminum substrates. Using hard rubber rollers will give good results achieved. With a suitable setting, a coating with a weight of 0.05 g / m 2 can be obtained. The porters had been grained electrochemically or by brushing.

The grained aluminum supports are aluminum supports with a Thickness of about 0.0; 5 cm (0.012 inch) which is electrochemically horned and are anodized so that they have a grain size as defined in Example 1.

The plates obtained in this way are then exposed and processed as in example 1β. With all six plates that the above mentioned Containing additives, compared to the two comparison plates which did not contain these additives, a pronounced one T-tendency against stronger image development noticed.

The plates thus obtained were stabilized using a physical developer with a ΔE of about further processed. For the production of this developer, the following solutions A, B and G were first prepared:

Solution A Solution B

Perroammonium sulfate - 78.4 g non-ionic surfactant ferric nitrate -] 52,> g (Synthrapol N) -0.8 7if «n« ^ os, m _Q Qn η ■ "Ionic surfactant citric acid - 80.0 g. (Alamine 4 ) - 0.8

Acetic acid - 0.8

Solution C

Silver nitrate

30 9 8 50/1007

Solutions A and B were then made up to 11 with water. Then 125 cm solution A, 25 cm solution B and 6 cm solution C made a mixture.

All six plates that contained the salt additives mentioned above, showed better images of improved density compared to the two comparison plates that did not contain these additives, especially in the areas of bright image points, for example the $ 5 image points on a 65 to 1550 line lapse (65-150 line screen). As a result, prints of improved quality are obtained in these areas of light dots, if these, the additives containing plates can be used for printing.

Three identical sets of six plates were produced with the difference that the plates after their production for 5 days, 2 weeks and 5 weeks, respectively, were subjected to accelerated aging. The ones scored with those last three sets of records Results are the same as those obtained with the first panels; i.e. the plates that have the above-mentioned additives show a marked tendency towards stronger images in the areas with bright points.

Example 27

A silver halide layer of the composition given in Example 16 is applied to an anodized aluminum carrier which is grained and anodized as in Example 1. the The plate produced in this way is then given a top coat of gelatine / Ammonium lactate of the following composition?

2 wt% gelatin 2166 2 wt % ammonium lactate

The topcoat has a wet thickness of 0.076 mm (3 mils). The so The produced plate is 20 seconds with a 250 W quartz / iodide lamp exposed from a distance of 76 cm (50 inches). Thieves-

309850/1007

exposed plate is then 3 minutes in a uniform stabilized 73 mV physical developer of the following composition:

0.105 m Fe (NH ₄ ) ₂ (SO ₄ ) ₂ 0.069 m Fe (NO,),
0.068 m AgNO,

$ 0.08 ionic surfactant (Armac 4-D) • $ 0.08 acetic acid

$ 0.08 non-ionic surfactant (Synthropol N)

The developed plate is washed and washed using the. for lithographic plate technique and then applied to a lithographic printing press. Under the use of With conventional printing paper, the printing plate produced more than 1,900,000 good quality prints. .

Examples 28 to 30 ...

To illustrate the benefit of using a low active developer, three developers of the following compositions would be made manufactured:

56 mV developer v.

Fe (NH ₄ ) ₂ (S0 ₄ ) ₂ - 0.109 m

Fe (NO,), -. 0.072 m

Tartaric acid - 0.054 m

Ionic Surfactant (Armac 12D) - $ 0.011

Non-ionic surfactant (Synthrapol N) - $ 0.011

AgNO, - 0.035 m

73 mV developer

Fe (NH ₄ ) ₂ (S0 ₄ ) 2 ~ .0.105 m

Fe (NO,), - 0.069 m

Tartaric acid - 0.053 m

Ionic Surfactant (Armac 12D) - $ 0.011

Non-ionic surfactant (Synthrapol N) - $ 0.011

AgNO, - 0.068 m

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Mon

121 mV developer

Pe (NH ₄ ) ₂ (S0 ₄ ) ₂ - 0.105 m

Pe (NO ^) ^ - 0.032 m

Tartaric acid - 0.053 m

Ionic Surfactant (Armac 12D) - $ 0.011

Non-ionic surfactant (Synthrapol N) - $ 0.011

AgNO ^ - 0.068 no

The developers were under the same conditions at normal Ambient conditions exposed to the atmosphere. The silver ion concentrations were used as a measure of the stability of the solution measured at different times:

Time, (Ag) concentration of developer days 56 mV

0 0.035

3 0.034

10 0.034

20 0.034

36 0.034

So the two developers with Δ Ε values of 56 and 73 mV were after the 36 days hardly degraded during the physical developer with a ΔΕ value of 121 mV already noticeable after 3 days was dismantled.

If the three solutions are used continuously, the degradation takes place more quickly than if the solutions were only left to stand will. However, the stability of the two developers of low ΔΕ is also considerably greater than that of the developer with 121 mV.

- 40 -

73 mV 121 mV 0.067 0.068 0.067 0.034 0.067 - 0.031 0.067 0.030 0.065 0.020

30 9850/1007

Claims (1)

Claims Photographic element made from a support with a layer from physical development nuclei or photosensitive material that generate such nuclei on the support capable, this layer containing a solvent-permeable binder and a thickness of less than about 2μ has and an activator for physical development contains, which causes accelerated development when in contact with a physical developer, and from a Material, preferably with the oxidized form of the reducing agent component of the physical developer responds, persists. 2. Element according to claim 1, characterized in that that the activator for physical development increases the rate of metal deposition or the optical density of at least about $ 20 compared to the same photographic element, caused when developing for the same. Time with a physical developer of the same composition he follows. 3. Element according to claim 1 or 2, characterized in that that the activator is an organic acid or a salt of an organic acid. 4. Element according to any one of claims 1 to J5, characterized characterized in that the activator is a material. that with the oxidized form of the reducing agent of the physical Developer's complexes is. -41 - ■ '. ... 309850/1007 223? . «Ft 5. .Element according to one of claims 1 to 4, characterized marked rejects that the photosensitive . Material silver halide or a photoconductor that works when exposed is reversibly activated with activating radiation is. - ■ ■ / 6 '. Element according to one of Claims 1 to 4, characterized in that · marked that the photosensitive Material is titanium dioxide, zinc oxide or silver halide. 7. Element according to any one of claims 1 to 6, characterized characterized in that the complex-forming agent (1) is a diacid or a solvent-soluble one Salt of such an acid, (2) a hydroxycarboxylic acid or a solvent-soluble salt of such Acid, (3) an amino acid, (4) an amine, or (5) a ß-diketone is. 8. Element according to claim 7 » characterized in that the activator is ammonium citrate, ammonium tartrate, t-butylamine tartrate, sodium hydrogen tartrate, sodium salicylate, sodium tartrate, calcium acetate, acetylacetone, sodium sulfate, triethanolamine, disodium ethylenediamine tetraacetic acid or ammonium lactate. 9. Element according to any one of claims 1 to 8, characterized marked ichnet that the activator for the physical development in one of the layer of physical evolution nuclei or photosensitive Material separate layer is present and that the binder is present in at least the outermost of these layers is. 309850/1007 ²²⁵⁷ Ό 10. Element according to any one of claims 1 to 9, characterized marked that it is still an ionic Surfactant, which upon contact of the photographic element, which contains an image pattern of development nuclei, with a physical developer the formation of metallic Images of improved quality and durability, when the element is used for printing on a printing press. 11. Element according to any one of claims 1 to 10, characterized marked that it was made of a printing plate a metallic support having a layer of a silver halide emulsion with an excess of halogen ions is on it. 12. The element of claim 11 wherein the silver halide emulsion is still contains a sulfur compound as a physical development initiator. 13. Element according to claim 11 or 12, thereby ge * I denote that the metallic support is an aluminum support which is grained and anodized and when used on a conventional offset lithographic printing press under ordinary conditions Can produce more than 100,000 copies on ordinary printing paper. 14. Element according to any one of claims 11 to 13 * characterized that the initiator for the physical evolution is a thiuram. 15. Element according to any one of claims 11 to 14, characterized characterized in that the metallic carrier 3 0 9850/1007 is grained, the grain size when tested on the OSRM a curve with a peak height A between about 0.25 and about 0.90 at a point B between about 0.35 and about 0.80 with a psi value / between about 0.40 and about 1.0 generated. 16. Element according to any one of claims 11 to 14, characterized characterized in that the metallic support is grained, the grain size when tested on the OSRM a curve with a peak height A between about 0.75 and about 0.85 at a point B between about 0.70 and about 0.75 at a psi value C between about 0.75 and about 0> 90 -generated. "17. A process for the formation of a metallic image in a photographic element which is sensitive to light from a support having thereon a layer of nuclei for physical development or photosensitive material capable of producing such nuclei and a physical development activator associated with this layer in sufficient quantity to increase the speed of development by at least 30% compared to the use of the same developer on the same photographic element but not containing such an activator, where -.'._ ■ - one in the photographic element, generates an image pattern of nuclei for physical development and brings the element with a stabilized uniform physical developer comprises a solution of metal ions and a reducing agent for that metal ions in contact. 18. The method according to claim 17, characterized in that that the physical developer is a low activity developer with a development rate which is not enough to make a usable _ 44 - 30 9850/1007 Printing plate or a photographic film transparency with an optical density of at least 1 when the photographic element is with the physical developer contacted for a time up to about 5 minutes will generate. 19. The method according to claim IJ, characterized in that the physical developer is a Δ Ε has less than about 100 mV. 20. The method according to any one of claims 17 to 19 * thereby it indicates that the physical developer has a Δ E between about 60 and about 100. -21. Method according to one of Claims 17 to 20, characterized marked rejects that the activator for the physical developer a complexing agent for the oxidized form of the reducing agent or a compound, which reacts with the oxidized form of the reducing agent, so that the effective concentration of these oxidized Shape is lowered is. 22. The method according to any one of claims 17 to 21, characterized characterized in that the layer of physical Development nuclei or photosensitive material. has a thickness below about 2μ. 23. The method according to any one of claims 17 to 22, characterized denotes that the physical developer is a solution of a silver compound, a ferrous compound and a Ferr! compound and the ΔE of the physical Developer is less than about 100 mV and the image formed is a silver image. 309 8 5 0/1007 24. The method according to claim 23 * characterized that the physical developer one . Has acidic pH and an ionic surfactant as a stabilizer for the developer as well as by the fact that the Activator for physical development the development speed increased by at least about $ 100 and wherein the rate of metal deposition upon contacting the physical developer with the photographic element that does not contain an activator is less than about 200 mg / m / min. 25. The method according to claim 24, characterized that the photographic element still has an ionic surfactant that is released upon contact with the photographic Element ", which contains an image pattern of development nuclei, with a physical developer, the formation of metallic images of improved quality and durability when used to print on a printing press. 26. The method according to any one of claims 23 to 25, d a du r c h marked rejects that layer of physical Development nuclei is formed by exposing a photosensitive layer to light. 27. The method according to any one of claims 23 to 26, characterized marked rejects that the photosensitive Layer contains a reversibly activatable photoconductor or silver halide. 28. The method according to any one of claims 23 to 26, characterized ge mark ze rejects that the photosensitive layer comprises a silver halide emulsion in excess Contains halogen ions and the photosensitive layer is deposited on an aluminum support. "46 - 3098 50/100 7 29. The method according to any one of claims 17 to 28, characterized marked rejects that the stage of development is extended so that a silver image that adheres firmly to the carrier and can be used as a printing plate, and this photographic element is then used as a printing plate on a lithographic printing press. 30. The method according to any one of claims 23 to 29, characterized characterized in that the activator for the ■ physical developer a complexing agent for the ferric ion of the physical developer or a material, that reacts with the ferric ion, namely (1) a Diarboxylic acid or a solvent-soluble salt of a such acid, (2) a hydroxycarboxylic acid or a solvent-like salt of such an acid, (3) an amino acid, (4) an amine or (5) a β-diketone. 31. The method according to any one of claims 17 to JO, d a d u r .c h characterized in that the activator for the physical developer ammonium citrate, ammonium tartrate, t-butylamine tartrate, sodium hydra tartrate, sodium alleylate, Sodium tartrate, calcium acetate, acetylacetone, sodium sulfate, Triethanolamine, disodium ethylenediamine tetraacetic acid or Is ammonium lactate. 32. The method according to claim 28, characterized that the photographic element still contains a sulfur compound as an initiator for the physical Contains development. 33. The method according to any one of claims 17 to 32, characterized characterized in that the copy medium is suitable for use as a printing plate. 34. The method according to claim 33 * characterized that the support of the printing plate is aluminum 3 0 9850/1007 in contact with an anodized and grained surface with the photosensitive layer. 35 «Method according to claim J> h, characterized in that the grain size of the aluminum carrier when tested on the OSRM has a curve with a peak height A between about 0.25 and about 0.90 at a point B between about 0, 35 and about 0.80 and has a psi C between about 0.40 and about 1.0. 36. The method according to claim ^ h, characterized in that g. ekennze lehnet, .that the grain size of the aluminum carrier. when tested on the OSRM, a curve with a peak height A between about 0.75 and about 0.85 at a point B between about 0.70 and about 0.75 with a psi C between about 0.75 and about 0.90 generated. - 48 - 309850/1007