Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: The invention relates to 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 cyanine dye having a betaine structure or having a betaine structure and containing an anion and having the formula (I) in which R1 to R8 independently of one another, are a hydrogen or halogen atom, a sulfonate, carboxylate, phosphonate, hydroxyl, (C1-C4)alkoxy, nitro, amino, (C1-C4)alkylamino, di(C1-C4)alkylamino group or a (C6-C10)aryl group which in turn may be substituted by one or more halogen atoms and/or one or more sulfonate, carboxylate, phosphonate, hydroxyl, (C1-C4)alkoxy, nitro, amino, (C1-C4)alkylamino and/or di(C1-C4)alkylamnino groups, R9 and R10 independently of one another, are a straight-chain or branched (C1-C6)alkyl, a (C7-C6)aralkyl or a (C6-C10)aryl group, each of which in turn may be substituted by one or more halogen atoms and/or on

Abstract: The invention relates to 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 cyanine dye having a betaine structure or having a betaine structure and containing an anion and having the formula (I) 1

Abstract: 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 (C1-C12) 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.

Abstract: 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, is described. A daylight-insensitive recording material which can be provided with an image using IR radiation and has a substrate and a layer comprising the mixture is also disclosed. After imagewise exposure, in particular to IR laser beams, and development with an aqueous alkaline solution, an offset printing plate can be formed therefrom.

Abstract: 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.

Abstract: 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.

Abstract: 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; anda silicone layer.

Abstract: 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 and D can be identical or different and are oxa-n- or -iso-alkylene, especially oxa-n- or -iso-(C.sub.1 -C.sub.5)-alkylene andl+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.

Abstract: 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.

Abstract: 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 areand D oxa-n- or -iso-alkylene, especially oxan- or -iso-(C.sub.1 -C.sub.5)-alkylene andl+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.

Abstract: 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.

Abstract: 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.

Abstract: 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 andR.sup.2 denotes hydrogen, (C.sub.1 -C.sub.6)n-alkyl or iso-alkyl or --OR.sup.1, and a relatively high-boiling alcohol.Compared with solvents of the prior art, the developing solvent of the present invention is non-toxic, can quickly be removed from the layer and has a high capacity for layer components.

Abstract: 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 andR.sup.2 denotes hydrogen, (C.sub.1 -C.sub.6)n-alkyl or iso-alkyl or --OR.sup.1.Compared with solvents of the prior art, the developing solvent of the present invention is non-toxic, can quickly be removed from the layer and has a high capacity for layer components.

Abstract: A process for producing an ozone-resistant flexographic printing form based on a photopolymerizable elastomeric mixture is described, which comprises applying to a developed and optionally post-treated flexographic printing form a treatment reagent containing as the essential constituent at least one 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 areand D oxa-n- or -iso-alkylene, especially oxa-n- or -iso-(C.sub.1 -C.sub.5)-alkylene and1+m+n+o is 3 to 40.

Abstract: A developing method for printing plates employing waterless offset processes is disclosed. The plates comprise a support coated with a photosensitive layer based on a diazonium salt polycondensation product and a super-imposed ink-repellent, crosslinked silicone elastomer layer, whereby said developer is characterized in that it contains a predominant proportion of compounds of the general formula R--(O--CH.sub.2 --CH.sub.2 --).sub.n --O--R, where R denotes C.sub.m H.sub.2m+1, n denotes an integer from 1 to 25 and m denotes an integer from 1 to 5. The present invention is particularly suitable for developing printing plates where the photosensitive layer comprises a diazonium salt polycondensation product comprising recurrent A--N.sub.

Abstract: A photosensitive printing plate for waterless offset printing is described which comprises a support, a photosensitive layer and an overlying, printing ink-repellent silicone rubber layer. The photosensitive layer contains a diazonium salt polycondensation product, a compound which can be polymerized by means of free radicals, preferably a (meth)acrylate, a photopolymerization initiator and optionally a binder. The printing plate has higher photosensitivity than corresponding plates whose photosensitive layer contains only a photopolymerizable mixture or only a diazonium salt polycondensation product.