Agfa-gevaert Ag

Agfa Gevaert Nv

Hoechst Aktiengesellschaft

Agfa-gevaert

Willi-Kurt Gries

Hans-Joachim Schlosser

Klaus-Juergen Przybilla

Klaus-Peter Konrad

Georg Pawlowski

Stephan J Platzer

Werner Frass

Raimund J Faust

Fritz-Feo Grabley

Guenter Jung

Claus-Peter Niesert

The invention relates to a recording material sensitive to IR radiation and having a substrate, a primer layer, an IR-absorbing layer and a silicone layer. The primer layer includes a mixture of an unmodified epoxy resin, an organic polymer having functional groups and a crosslinking agent which reacts with the epoxy resin and the functional groups of the organic polymer. The primer layer preferably contains at least one pigment, in particular inorganic pigments. For the production of a printing plate for waterless offset printing, the recording material is exposed imagewise to IR radiation and is then freed from the ablated layer components by washing with water or an aqueous solution. Preferably the radiation is IR laser radiation. The primer layer according to the invention results in particularly good adhesion of the IR-absorbing layer to the substrate without hindering the removal of the exposed parts of the IR-absorbing layer during development.

Radiation-sensitive recording material for the production of waterless offset printing plates

Photocurable elastomeric mixture and recording material obtained therefrom for the production of relief printing plates

A recording material is provided, having, in this sequence, a support, a radiation-sensitive layer and a silicone layer. The radiation-sensitive layer contains, as a radiation-sensitive component, a diazonium salt polycondensation product and, as a binder, a homopolymer of (C,-C,) alkyl vinyl ether units and/or a copolymer including at least 5 mol-% of such units, and being free of aliphatic hydroxyl groups. In a process to produce a printing plate for driographic offset printing, this recording material is exposed imagewise and subsequently developed using water or an aqueous solution.

Radiation-sensitive recording material for the production of driographic offset printing plates

The invention relates to a photocurable, negative-working mixture and a recording material which is obtained therefrom and which is suitable for the production of elastic relief printing plates. The mixture contains a) an amphiphilic elastomeric binder, b) a free-radical-polymerizable compound which is compatible with the binder and which has at least one terminal, ethylenically unsaturated group and a boiling point of over about 100.degree. C. at normal pressure and c) a compound or a combination of compounds which is capable of initiating the polymerization of the compound b) on exposure to actinic light. The binder is made up of the segments A, B, C and X, where:

Photocurable elastomeric mixture and recording material obtained

The invention relates to a recording material having a plate- or sheet-like substrate, at least one IR-absorbing layer, which comprises at least one IR-absorbing component and at least one polymeric, organic binder and decomposes under the action of IR laser radiation or changes so that its adhesion to the silicone top layer decreases, and a top layer comprising a cured silicone rubber. The substrate comprises an oxidizable metal or one of its alloys and, at least on the side facing the IR-absorbing layer, is roughened and is covered with a layer of an oxide of the metal. The invention also relates to a process for the production of a waterless offset printing plate and to the printing plate itself which is produced from the recording material according to the invention and in which the hydrophilic surface of the oxide layer is ink-carrying and the oleophobic top layer is ink-repellent.

Laser-imagable recording material and printing plate produced therefrom

A photosensitive mixture which contains a polycondensation product of an aromatic diazonium salt, a water-soluble amphophilic polymeric binder having a mean molecular weight M.sub.w of 5000 to 100,000 and a nonionic surface-active compound having a molecular weight of 150 to 2000 is suitable for the production of printing plates, particularly offset printing plates, which can be developed with pure water and are notable for a rapid ink take-up and long print run.

Photosensitive mixture comprising a diazonium salt, an amphophilic

Compounds of the general formula I: (SIL--X--).sub.m IN (I), in which SIL is a radical of the formula Si(R.sup.1)(R.sup.2)(R.sup.3), where R.sup.1 is an alkyl, haloalkyl or alkoxy radical of 1 to 8 carbon atoms, an alkenyl radical, an alkenyloxy or acyloxy radical of 2 to 8 carbon atoms, an aryl or aryloxy radical of 6 to 10 carbon atoms, or a dialkyl-, diaryl- or alkylaryl-methyleneaminooxy radical having C.sub.1 -C.sub.4 -alkyl or C.sub.6 -aryl groups; and R.sup.2 and R.sup.3 are identical or different radicals with the meaning of R.sup.1 or X--IN; X is a group C.sub.n H.sub.2n ; IN is the radical of a compound which is active as a photoinitiator or photosensitizer and which has at least one carbonyl group located on an aromatic nucleus; m is a number from 1 to 4; and n is a number from 2 to 12, or of the formula II: Si.sub.o O.sub.o-1 (--X--IN).sub.p R.sup.4.sub.2o+2-p (II), in which R.sup.4 is a radical with the meaning of R.sup.1, and two or more radicals R.sup.4 may be the same as or different from one another; o is a number from 2 to 20,000; and p is a number from 1 to o, and the symbols X and IN are as defined above, the group X being attached to an aromatic carbon atom which is positioned ortho to the carbonyl group of IN. The compounds are prepared by reacting a compound IN--H with a compound SIL--X' or a compound Si.sub.o O.sub.o-1 (--X').sub.p R.sup.4.sub.2o+2-p in the presence of a ruthenium compound. They are suitable as radical-forming photoinitiators or as photosensitizers in silicone-containing photopolymerizable mixtures, in particular for the production of waterless-printing planographic printing plates.

Silicone-compatible photoinitiators, and photosensitive mixtures

A radiation-sensitive recording material comprising: a base; a radiation-sensitive layer comprising a diazonium salt polycondensation product and 3 to 50% by weight, relative to the total weight of the radiation-sensitive layer, of a mineral acid; and a silicone layer.

Water developable diazonium and mineral acid containing recording

A photosensitive material for the production of offset printing plates which contains a) a coating base which is composed of aluminum or an aluminum alloy and is suitable for offset printing, b) a hydrophilic coating containing an organic polymer and a free-radical-polymerizable compound and having a coating weight in the range from 0.001 to 1 g/m.sup.2, c) a photopolymerizable coating containing (1) a polymeric binder, (2) a free-radical-polymerizable compound and (3) a compound or a combination of compounds which is capable of initiating the polymerization of the compound (2) on exposure to actinic radiation, and d) a transparent covering sheet, the adhesion of the photopolymerizable coating (c) to the hydrophilic coating (b) and/or the covering sheet (d) being altered by exposure. The material is processed to form the printing plate by imagewise exposure and peeling the covering sheet (d) together with the unexposed areas of the coating (c) off the coating base (a) ('peel apart'). Printing plates having good resolution and high run performance are obtained.

Photosensitive material and method of producing offset printing plates

A process for the production of a lithographic printing plate is described, in which a photosensitive material comprising a substrate suitable for lithographic printing, a hydrophilic intermediate layer, a photopolymerizable layer which changes its adhesion to the hydrophilic layer and/or to the cover sheet on exposure to light and a transparent cover sheet provided with an exposure mask which is non-transparent to actinic light is exposed to actinic light through the exposure mask, and the photopolymerizable layer is developed to give the image by peeling off the cover sheet from the substrate. The process is carried out in all stages without the use of chemicals and gives printing plates having good oleophilic properties and a long press life.

Process for the production of a lithographic printing plate through

A photosensitive material useful for the production of lithographic printing plates, which contains (a) a support suitable for lithographic printing plates, (b) a hydrophilic layer which contains a crosslinkable organic polymer or is a layer formed by crosslinking such a polymer, (c) a photopolymerizable layer and (d) a transparent cover film, the adhesion of the photopolymerizable layer (c) to the hydrophilic layer (b) and/or to the cover film (d) being changed by exposure. The material permits the production of lithographic printing plates having high printing performance without the use of liquid processing agents.

Photosensitive material for the production of lithographic printing

Process for the production of lithographic printing plates utilizing

A light-curable elastomeric mixture is described, containing

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Wiesbaden, Germany

Willi-Kurt Gries