Abstract: The invention relates to a radiation-curable mixture for generating relief structures, comprising a) at least one functionalized, part-hydrolyzed polyvinyl acetate comprising (i) vinyl alcohol units, (ii) vinyl acetate units, and (iii) vinyl acrylate units, where the vinyl acrylate units, which can be substituted, have the general structure where R is hydrogen or a linear or branched aliphatic or heteroaliphatic radical having 1 to 12 carbon atoms, or a cycloaliphatic, heterocyclic or aromatic radical having 3 to 12 carbon atoms, as component A, b) at least one initiator as component B, c) at least one ethylenically unsaturated compound different from component A, as component C, d) one or more adjuvants as component D, wherein the amount of vinyl acrylate units (iii) in the functionalized, part-hydrolyzed polyvinyl acetate a), based on all the units (i), (ii), and (iii), is 0.1 to <3 mol %, and component D comprises an additive capable of hydrogen bonding, in an amount of 0.

Abstract: The invention relates to a cylinder (10) which is set up for application of at least one hollow cylinder, the cylinder (10) having a layer structure which comprises in this order, from inside to outside, a base layer (12) or a cylinder core, a first compressible layer (14), a filling layer (16), an interlayer (18), a second compressible layer (20) and an outer layer (22), the outer layer forming a lateral surface of the cylinder. The invention further relates to arrangements comprising at least one such cylinder (10) and further cylinders.

Abstract: A digitally imageable, photopolymerizable relief precursor at least comprising, arranged one above another in the order stated, (A) a dimensionally stable carrier; (AH) optionally, an adhesion-promoting layer; (B) a relief-forming layer, at least comprising a crosslinkable elastomeric binder, a first ethylenically unsaturated monomer, and a photoinitiator; (C) at least one interlayer, at least comprising a first, non-radically crosslinkable elastic polymer; (D) a laser-ablatable mask layer, at least comprising a second, non-radically crosslinkable elastic polymer, a UVA light-absorbing material, and an IR light-absorbing material; and optionally (E) a removable cover layer; characterized in that the layer (C) and optionally the layer (D) comprise at least one second ethylenically unsaturated monomer.

Abstract: A method of thermal development of flexographic printing elements, having steps of: fixing a relief precursor a movable support; repeatedly moving the support in a multitude of movement cycles; heating the relief precursor to a temperature sufficient to cause the uncured portions of the photopolymer layer to soften or liquefy; contacting with a development medium; Single movement cycles are carried out with different heating powers and different contacting with the developing medium such that one may improve the registration accuracy of the printing element, ease removal of functional layers, smoothen the relief plate precursor surface, and address heat build-up problem.

Abstract: A method for the production of functionalized partially hydrolyzed polyvinyl acetate comprising vinyl alcohol, vinylacetate and functionalized vinyl alcohol units by reacting in a melt a partially hydrolyzed polyvinyl acetate as component A with a reactive compound carrying at least one ethylenically unsaturated group and at least one reactive group reactive with hydroxyl or acetate groups as component B, in the presence of at least one stabilizer as component C and in the presence of at least one catalyst selected from the group consisting of tertiary amines and nitrogen-containing heterocycles as component D, the method comprising the steps: feeding the components into a mixing device capable of heating, melting and mixing components A, B, C and D, heating, melting and mixing components A, B, C and D in the device to give a melt and reacting components A and B in the melt.

Abstract: The invention relates to a process for the production of relief printing plates, where a carrier with a polymeric substrate layer is provided and a relief is formed layer-by-layer on a surface of the substrate layer, where the relief is formed by means of a) single or multiple application of a liquid comprising at least one reactive monomer to the surface of the substrate layer, b) diffusion of the reactive monomer into the polymeric substrate layer for a prescribed exposure time and c) hardening of the relief, where in step a) the liquid is applied in accordance with an image to the surface and where, after the prescribed exposure time of step b), any liquid that remains on the surface, having not diffused into the material, is removed from the surface, and in step c) the relief that is hardened comprises the polymer of the substrate layer and reactive monomer that has diffused into the material.

Abstract: A method for assembling a hollow cylinder on, or removing a hollow cylinder from, a further cylinder. The hollow cylinder includes a body with openings for creating an air cushion within a first portion of a shell and a second portion of the shell is gas-impervious or has openings for creating an air cushion of a reduced quantity and/or size compared to the first portion. The openings are connected to a gas feed and a gas inlet inside the body. The further cylinder has openings on a shell and gas is fed though the openings via an internal gas supply. An assembly method includes providing the hollow cylinder, applying a seal to the first portion to prevent escape of gas from the first portion, providing the further cylinder, applying gas to the further cylinder so that gas escapes from the openings, and pushing the hollow cylinder onto the further cylinder.

Abstract: A cylinder is arranged to receive one or more hollow cylinders on an outer surface of the cylinder. The cylinder has at least one movable stop with at least one movable element. In an idle position the at least one movable element does not protrude beyond the outer surface of the cylinder and allows hollow cylinders to be slid over the cylinder, and in an active position it protrudes beyond the outer surface of the cylinder and acts as a mechanical stop for hollow cylinders. The at least one movable element can be moved from the idle position to the active position, and vice versa, by means of a rotary movement. A method for positioning a hollow cylinder on a cylinder of this kind.

Abstract: The present invention relates to an apparatus (10) for developing printing precursors (11) comprising a developing station (20) comprising a rotating drum (22) having a fixation mechanism (24) for the precursor (11) and at least one brush (26). The apparatus (10) further comprises a pre-cleaning station (30) and a first transport mechanism (12), the first transport mechanism (12) being configured for transporting the precursor (11) through the pre-cleaning station (30) and, after the precursor (11) has passed the pre-cleaning station (30), to the developing station (20). Further aspects relate to a method for developing a printing precursor using such an apparatus.

Abstract: A photosensitive composition of a developable relief precursor includes at least one ethylenically unsaturated monomer as component E, at least one photoinitiator or photoinitiator system as component P, at least one water soluble and/or water dispersible binder as component B, and optionally, one or more additives as component A. Component E includes at least one ionic group and component E is present in an amount of 0.1 to 30 wt %, based on the total weight of the photosensitive composition.

Abstract: A photosensitive composition of a developable relief precursor, comprising: at least one copolymer as component C, at least one ethylenically unsaturated compound as component U, at least one photoinitiator or photoinitiator system as component P, at least one water soluble and/or water dispersible binder as component B, wherein the at least one copolymer as component C is an at least partially hydrolyzed ethylene vinyl acetate copolymer, comprising —CH2—CH2— groups and wherein the content of said —CH2—CH2— groups in the partially hydrolyzed ethylene vinyl acetate copolymer is lower than 20 mol %, preferably lower than 15 mol %, more preferably lower than 10 mol %.

Abstract: The invention relates to a method for producing pictorial relief structures on a layer construction. The method comprises the provision of a layer construction having a substrate layer. After this, at least one fluid containing at least one first reactive component is applied pictorially to the substrate, wherein the pictorial application takes place in the form of a plurality of droplets with a droplet volume of less than 2 ?l, and wherein the droplets are positioned pictorially. After this, there is an at least partial diffusing of the at least one first reactive component into the substrate layer for a predefined exposure time and/or an at least partial diffusing of at least one second reactive component into the pictorially positioned droplets of fluid for a predefined exposure time, wherein the substrate layer comprises the at least one second reactive component.

Abstract: Described herein is an adapter sleeve for adapting the internal diameter of cylindrical hollow cylinders to the external diameter of a cylindrical roller, comprising a sleeve body with (as viewed from the inside to the outside) a deformable base sleeve, optionally an intermediate layer and a top layer. The adapter sleeve furthermore contains a first gas distribution system and a second gas distribution system, which are connected to a gas inlet. The first gas distribution system is connected to at least one first gas outlet, which opens on an outer lateral surface of the adapter sleeve. The second gas distribution system has a cavity, which is designed, when supplied with a pressurized gas, to transmit pressure from the inside to the deformable base sleeve in such a way that the internal diameter of the sleeve body is reduced, at least in a partial region of the adapter sleeve, by a deformation of the base sleeve.

Abstract: A cylinder is arranged to receive one or more hollow cylinders on an outer surface of the cylinder. The cylinder has at least one movable stop with at least one movable element. In an idle position the at least one movable element does not protrude beyond the outer surface of the cylinder and allows hollow cylinders to be slid over the cylinder, and in an active position it protrudes beyond the outer surface of the cylinder and acts as a mechanical stop for hollow cylinders. The at least one movable element can be moved from the idle position to the active position, and vice versa, by means of a rotary movement. A method for positioning a hollow cylinder on a cylinder of this kind.

Abstract: The invention relates to a laser-ablatable mask film for the exposing of relief printing plates and screen printing stencils, comprising at least (i) a dimensionally stable base sheet, (ii) a UV-transparent adhesion layer, and (iii) a laser-ablatable mask layer, characterized in that the laser-ablatable mask layer (iii) comprises a) a binder comprising a crosslinked polyvinyl alcohol, b) a material which absorbs UV/VIS light and IR light, and c) optionally an inorganic filler.

Abstract: The invention relates to an exposure apparatus (1) for exposing plate-shaped materials (2). The plate-shaped material (2) has a first side (3) and a second side (4) that lies opposite the first side (3). The exposure apparatus (1) comprises a first exposure unit (10) and a conveyor unit (30), wherein the first exposure unit (10) comprises at least one segment with a light source and has an embodiment so as to be rotatable about an axis (14), and the first exposure unit (10) and the conveyor unit (30) are configured in such a way that the first side (3) of the plate-shaped material (2) is supplied for an exposure in a first position (11) of the exposure unit (10) and the second side (4) of the plate-shaped material (2) is supplied for an exposure in a second position (12) of the exposure unit (10). Further aspects of the invention relate to methods for exposing plate-shaped material and a printing plate that was produced from a plate-shaped material according to any one of the methods.

Abstract: The invention relates to a method for generative production of relief printing plates, wherein a support with a polymeric substrate layer and a laser-ablatable mask layer is provided, the polymeric substrate layer containing a first binder. A mask with openings corresponding to pixels is produced by imagewise laser ablation of the mask layer. A liquid containing a reactive monomer is then applied over the surface of the mask-covered polymeric substrate layer, and the liquid or the reactive monomer diffuses through the openings of the mask into the polymeric substrate layer for a defined exposure time so as to form a relief. The excess liquid or the excess monomer and optionally the mask are removed from the surface, and the resulting relief is fixed by crosslinking.

Abstract: A laser-engravable pad printing plate comprising at least (a) a metal support, (b) an adhesion layer, (c) a laser-engravable recording layer having a layer thickness of 20 ?m to 200 ?m, (d) a cover film, characterized in that the laser-engravable recording layer (c) comprises (c1) 40 to 95 wt % of a polyvinyl alcohol, (c2) 5 to 50 wt % of an IR absorber, (c3) 0 to 30 wt % of an inorganic filler, (c4) 0 to 20 wt % of a crosslinker, and (c5) 0 to 10 wt % of further additives.

Abstract: A method for producing flexographic printing plates, using a photopolymerizable flexographic printing element having, arranged one atop another, a dimensionally stable support, a photopolymerizable, relief-forming layer, an elastomeric binder, an ethylenically unsaturated compound, and a photoinitiator, and optionally a rough, UV-transparent layer, a particulate substance, and digitally imagable layer. The method includes: (a) producing a mask by imaging the digitally imagable layer, (b) exposing the photopolymerizable, relief-forming layer through the mask with actinic light, and photopolymerizing the image regions of the layer, and (c) developing the photpolymerized layer by washing out the unphotopolymerized regions of the relief-forming layer with an organic solvent, or by thermal development.

Abstract: A device for producing flexographic printing plates starting from digitally imagable flexographic printing elements, with which at least the method steps of reverse exposure, main exposure, development using washout media, drying, and aftertreatment can be carried out in automated form, the device comprising at least two different transport devices with which the flexographic printing elements or plates, respectively, are transported through the device. A method for producing flexographic printing plates using said device.