Hoechst Aktiengesellschaft

E.i. Dupont De Nemours and Company

Agfa Gevaert Nv

Agfa-Gevaert Ag

Agfa-Gevaert

Afga-Gevaert

Hans-Joachim Schlosser

Heinz Herrmann

Willi-Kurt Gries

Guenther Schoen

Andreas Elsaesser

Fritz-Feo Grabley

Werner Frass

Joachim Gersdorf

Otfried Gaschler

Klaus-Peter Konrad

Joerg Jung

Thomas Leichsenring

Thorsten Lifka

Engelbert Pliefke

Klaus-Juergen Przybilla

Rudolf Petry

Karin Maerz

Susanne Billino

Dieter Bohm

Helmut Haberhauer

Sabine Kosack

Raimund-Josef Faust

Armin Pink

Joerg Strack

This present invention discloses a photopolymerisable mixture comprising a polymer binder, a radically photopolymerisable component containing at least one photooxidisable group, a polyethylene glycol di(meth)acrylate containing 2 or more ethylene glycol units, a photoreducible dye and a metallocene. This mixture can be used for preparing high-speed light-sensitive recording materials showing a particularly high resolution, especially for small negative types.

Photopolymerizable mixture and recording material prepared therewith

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

The invention relates to a pigment dispersion which contains at least one polymer containing polyvinyl alcohol, polyvinyl ether an/or polyvinyl acetal units and at least one polymer based on acrylate, wherein the weight ratio is generally 1:10 to 10:1, preferably 4:1 to 1:4. This dispersion is used in positive- or negative-working and reversible photosensitive mixtures for the preparation of recording materials.

Stable pigment dispersion and photosensitive recording material prepared therewith

Radiation-sensitive mixtures comprising IR-absorbing cyanine dyes having a betaine structure or having a betaine structure and containing an anion, and recording materials prepared therewith

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

A positive-working, radiation-sensitive mixture which contains an organic, polymeric binder which is insoluble in water but soluble or at least swellable in aqueous alkaline solution and at least one IR-absorbing dye,

Radiation-sensitive mixture comprising IR-absorbing, anionic cyanine dyes and recording material prepared therewith

The invention relates to a recording material having a substrate and a radiation-sensitive, water-insoluble layer which contains a component absorbing IR radiation and which, after the action of infrared radiation, becomes soluble or at least swellable in an aqueous alkaline developer. A top layer which is opaque to white light but transparent to radiation in the IR range and can be removed with water or an aqueous solution is present on the radiation-sensitive layer. The recording material is substantially insensitive to daylight. By imagewise exposure to IR radiation and subsequent development with an aqueous alkaline developer, it is possible to produce a printing plate for offset printing from the recording material. If the top layer is washed off beforehand, the recording can also be carried out using conventional UV radiation.

Thermally recordable material insensitive to white light

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 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

The invention describes a developing solvent for layers which are crosslinkable by photopolymerization and contain a binder based on an elastomeric polymer, a photopolymerizable monomer compatible therewith and a photoinitiator. The developing solvent comprises an aromatic compound of the general formula I ##STR1## wherein R.sup.1 to R.sup.4 are the same or different and denote hydrogen, (C.sub.1 -C.sub.5)n-alkyl or iso-alkyl and R.sup.1 and R.sup.2, provided that R.sup.1 and R.sup.2 are directly adjacent, may also form a cycloaliphatic or aromatic ring having 5 or 6 carbon atoms as ring members which are preferably non-substituted, provided that the sum of carbon atoms of the substituents and ring members is from 9 to 13. Compared with solvents of the prior art, the developing solvent of the present invention is non-toxic, can quickly be removed from the layer, has a high capacity for layer components and is capable of developing plates based on nitrile rubber.

Developing solvent for layers which are crosslinkable by

A photopolymerizable elastomeric mixture for producing ozone-resistant flexographic printing forms is disclosed which contains an elastomeric binder, an olefinically unsaturated compound polymerizable by free radicals, a photoinitiator, and a polyglycol ether of the general formula I ##STR1## in which R.sub.1 and R.sub.2 are alkyl, especially (C.sub.1 -C.sub.3)-alkyl,

Photopolymerizable elastomeric mixture and recording material containing

A photopolymerizable elastomeric mixture for producing ozone-resistant flexographic printing forms is disclosed which contains an elastomeric binder, an olefinically unsaturated compound polymerizable by free radicals, a photoinitiator, and a polyglycol ether of the general formula I ##STR1## in which R.sub.1 and R.sub.2 are alkyl, especially (C.sub.1 -C.sub.3)-alkyl, R.sub.3 is hydrogen or alkyl, especially (C.sub.1 -C.sub.3)-alkyl, A, B, C can be identical or different and are and D oxa-n- or -iso-alkylene, especially oxan- or -iso-(C.sub.1 -C.sub.5)-alkylene and l+m+n+o is 3 to 40. A recording material containing the photopolymerizable mixture as well as a process for producing a flexographic printing form are likewise described. The flexographic printing form obtained shows improved ozone resistance as compared with forms of the state of the art.

A continuous process for the manufacture of photopolymer plates having a precise and constant thickness in which the components of the photopolymer layer are melted in a screw extruder, the melt is conveyed to the sheet die by means of a gear pump and then into a roll gap of a calender, wherein the melt leaving the sheet die does not form a rotating bead in the calender gap downstream therefrom. The photopolymer plates prepared in this manner have high homogeneity of the components of the photopolymerizable mixture, have a highly precise and constant thickness, are transparent, do not tend to form specks and guarantee a long shelf life.

Process for the manufacture of photopolymer plates

The invention describes a developing solvent for layers which are crosslinkable by photopolymerization and contain a binder based on an elastomeric polymer, a photopolymerizable monomer compatible therewith and a photoinitiator. The developing solvent comprises a phenol ether of the general formula I ##STR1## wherein R.sup.1 denotes (C.sub.1 -C.sub.6)n-alkyl or iso-alkyl, cycloalkyl or (C.sub.6 -C.sub.12)-aryl and

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Wiesbaden, Germany

Hans-Joachim Schlosser