Hoechst Aktiengesellschaft

Vereinigte Aluminum-werke Aktiengesellschaft

Gerhard Sprintschnik

Joachim Stroszynski

Kurt Reiss

Walter Niederstaetter

Gunther Scharf

Walter Niederstatter

Gerhard Buhr

Rudolf Neubauer

Fritz Uhlig

Ulrich Simon

Wolfgang Von Asten

Barbara Grzemba

Reiner Beutel

Wolfgang V Asten

Dieter Bohm

Barbara Grzembra

Walter Niderstatter

The invention is directed toward a base material for aluminum offset printing plates having improved heat stability comprising an aluminum alloy consisting of from about 0.2 to about 0.6% by weight of iron, less than about 0.25% by weight silicon and copper combined, from about 0.1 to about 0.3% by weight manganese and the remainder being aluminum and trace production impurities, said base material further characterized as containing secondary precipitates in the form of phases of the Al Mn Si: Al Fe: Al Mn type which bear a ratio to one another of from about 1:1:2 to about 1:1:3, the mean particle size being from about 0.25 to about 0.010 micron with a maximum particle size of less than about 0.3 micron and further containing a precipitation structure with a degree of dispersion of less than about 50 phases per cubic micron and a process for producing such material. The sheet material according to this invention may be uniformly roughened in either HCl or HNO.sub.3 electrolyte baths under very similar process parameters.

Process for producing base material for an aluminum offset printing plate

The invention is directed toward a base material for aluminium offset printing plates having improved heat stability comprising an aluminum alloy consisting of from about 0.2 to about 0.6% by weight of iron, less than about 0.25% by weight silicon and copper combined, from about 0.1 to about 0.3% by weight manganese and the remainder being aluminum and trace production impurities, said base material further characterized as containing secondary precipitates in the form of phases of the Al Mn Si: Al Fe: Al Mn type which bear a ratio to one another of from about 1:1:2 to about 1:1:3, the mean particle size being from about 0.25 to about 0.010 micron with a maximum particle size of less than about 0.3 micron and further containing a precipitation structure with a degree of dispersion of less than about 50 phases per cubic micron and a process for producing such material. The sheet material according to this invention may be uniformly roughened in either HCl or HNO.sub.3 electrolyte baths under very similar process parameters.

Base material for an aluminum offset printing plate

The process for manufacturing materials, in the form of sheets, foils or webs, comprised of chemically, mechanically and/or electrochemically roughened and anodically oxidized aluminum or an aluminum alloy, which process is performed with two hydrophilizing post-treatment steps. In post-treatment step (a) a supported aluminum oxide layer is treated with an aqueous alkali metal silicate solution which optionally contains alkaline earth metal ions, and in step (b) the aluminum oxide layer is separately treated with an aqueous solution containing at least one organic polymer comprised of vinylphosphonic acid and/or vinylmethylphosphinic acid monomers, such as polyvinylphosphonic acid. Treatment of the aluminum oxide layer is accomplished by means of immersion and/or electrochemically. Materials prepared by this process are particularly useful as supports for offset printing plates, showing an improved resistance to alkali and a reduced tendency to adsorb dyestuff.

Process for a two-stage hydrophilizing post-treatment of aluminum oxide

Disclosed is a sheet, foil or strip material comprising aluminum or an alloy thereof, which is first mechanically and then electrochemically roughened on one or both surfaces to produce the following parameters:

Sheet material of mechanically and electrochemically roughened aluminum,

Device for continuously anodically oxidizing aluminum strips on one

Disclosed is a process for the production of a material in the form of a plate, a foil or a strip, from aluminum or an alloy thereof, which has been chemically, mechanically and/or electrochemically roughened. The process comprises a two-stage oxidation involving a first stage (a) which is performed in an aqueous electrolyte having from about 60 to 180 g/l of phosphoric acid, at a temperature of the electrolyte bath of about 47.degree. to 70.degree. C. and at a voltage of about 36 to 80 V and a second stage (b) which is performed in an aqueous electrolyte having from about 60 to 300 g/l of sulfuric acid, at a temperature of the electrolyte bath of about 30.degree. to 65.degree. C. and at a voltage of about 15 to 35 V. Also disclosed is an offset-printing plate, having a radiation-sensitive coating and a support material produced by the process described above.

Two-stage process for the production of anodically oxidized aluminum

The invention relates to a developer mixture for developing exposed, light-sensitive reproduction layers which contain a diazonium salt polycondensation product. The mixture comprises water, a salt of an alkanoic acid and a surfactant and contains 0.5 to 15 percent by weight, in particular 1 to 10 percent by weight, of at least one salt of an alkanoic acid having 8 to 13 carbon atoms and 0.5 to 20 percent by weight, in particular 1 to 12 percent by weight, of at least one low-foaming, nonionic surfactant. These surfactants preferably include optionally modified block polymers formed from ethylene oxide and propylene oxide. The invention also relates to a process for developing negative-working reproduction layers, of the composition indicated above, with the developer mixture according to the invention.

Developer mixture and process for developing exposed negative-working

This invention relates to a developer mixture for washing out light-sensitive copying layers previously exposed in imagewise manner and containing a polymer of an N-vinyl amine, of vinyl alcohol or of a vinyl alcohol derivative, an alcohol being water-soluble in an amount less than 10% by weight, and water as the main constituent, the mixture containing as said polymer a copolymer which is water-soluble or which can be dispersed in water to form a stable dispersion, composed of (a) hydrophilic units of the formula I: ##STR1## wherein A is O-R or ##STR2## R is a hydrogen atom or a methyl group; R.sub.1 is a hydrogen atom, an alkyl group or an alkoxy alkyl group having 1 to 10 carbon atoms each or an aryl group with 6 to 10 carbon atoms; R.sub.2 is an alkyl group or an acyl group having 1 to 5 carbon atoms each, and wherein a homopolymer of the hydrophilic units is water-soluble and of (b) hydrophobic units of vinyl monomers whose homopolymer is water-insoluble and which have an aromatic or a long-chain aliphatic group as the substituent, the proportion of the hydrophobic units being sufficient to ensure that an 0.1% aqueous solution of said copolymer has a surface tension of not more than 50 mN/m and that the quantity of said copolymer is at least sufficient to emulsify any quantity of alcohol exceeding the solubility limit. The invention also relates to a process for developing exposed light-sensitive copying layers using said developer mixture.

Developer mixture for developing exposed light-sensistive copying layers

This invention relates to a light-sensitive copying material comprising a coating support and an optically homogeneous light-hardenable coating which contains a condensation product of an aromatic diazonium salt and a water-insoluble macromolecular polymer, wherein the coating is applied from a stable dispersion of the water-insoluble polymer under conditions such that after drying an optically homogeneous coating is formed. The invention also relates to a process for the manufacture of a light-sensitive copying material containing the optically homogeneous light-hardenable coating.

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Taunusstein, Germany

Gerhard Sprintschnik