In a method for operating a rotary printing press, preferably a flexographic printing press that processes webs, disturbances of a rotating printing cylinder are detected and reduced by changing the printing speed. Here, the disturbances are detected at an actuating drive of the printing cylinder. This leads to a cost-efficient way of printing without disturbances.

Wettable structures that retain liquid layers are defined at surfaces of substrates. The wettable structures include grooves or ridges that are spaced apart by between 10 nm and 10 μm and can be defined in substrate or in a layer formed on a surface of the substrate. In typical examples, wettable structures are defined with hydrophobic materials or at hydrophobic surfaces and produce hydrophilic surfaces.

A heating circuit having an array of switching heating elements (e.g., field effect transistors, thin film transistors) provides a transient heat pattern over a surface (e.g., substrate, imaging member surface, transfer roll surface) moving relative to the heating circuit, to produce a pixelated heat image and heat a target pattern on the surface. Heat is generated by current flow in the heating elements, and the power developed by the heating circuit is the product of source-drain voltage and current in the channel. Digital addressing may accomplished by matrix addressing the array. Current may be supplied along data address lines by an external voltage controlled by digital electronics understood by a skilled artisan to provide the desired heat at a respective heating element pixels addressed by a specific gate line. The circuit may include a current return line that may be low resistance, for example, by using a 2-dimensional mesh.

A system for the replacement of sleeves that can be slipped on arbors of ink transfer rollers of at least printing machine has a storage device, in which the sleeves not being used in current ink transfer can be stored, and a transport device, with which several sleeves can be transported to the printing machine. The system has a transfer device the facilitates the transfer of the sleeves between the storage device and/or the transport device and the arbors of the ink transfer rollers, and/or between the storage device and the transport device.

A device for measuring elevations of a surface of a rotary body embodied as a cylinder, roller, sleeve, plate or flexographic printing plate for graphic industry machines includes a first motor for rotating the rotary body about an axis of rotation and a measuring device for contactless measurement which is part of or integrated into a mounter for printing plates. The measuring device allows the printing forme to be measured and analyzed to check mounting quality and to detect diameter differences. The measuring device preferably further includes a reference object, such as a wire tautened in an axially parallel direction, a second motor and, if desired, a further second motor for adjusting the measuring device and/or the reference object in a direction perpendicular to the axis of rotation. The device provides a fast way of measuring the elevations, such as flexographic print dots, with great accuracy.

A method of operating a flexographic printing press having a printing cylinder carrying a sleeve with at least one flexographic printing forme or a flexographic printing cylinder, and an impression cylinder, includes adjusting contact pressure between the printing cylinder or the flexographic printing cylinder and the impression cylinder by motor. The adjustment is made in an automated way as a function of a dot density of the flexographic printing forme, i.e. of a location-dependent density of printing elevations on the flexographic printing forme or data computationally derived therefrom. A cost-efficient way of producing high-quality prints in an industrial flexographic printing process is thus provided. In addition, the method advantageously provides further automation of the printing process. A flexographic printing press, a flexographic printing press system, and a flexographic printing forme or sleeve for a flexographic printing forme are also provided.

A method operates a flexographic printing press. The press contains a printing cylinder carrying a sleeve with at least one flexographic printing forme or a flexographic printing cylinder and an impression cylinder forming a printing nip with the printing cylinder to print on a web of printing substrate. The method includes automatically adjusting the transport speed of the web of printing substrate as a function of a dot density of the flexographic printing forme, i.e. of a location-dependent density of printing elevations on the flexographic printing forme, or of data computationally derived therefrom, or as a function of gaps of the flexographic printing forme or printing cylinder or data computationally derived therefrom. The printing press advantageously provides a cost-efficient way of producing high-quality prints in an industrial flexographic printing process while avoiding undesired vibration. In addition, the method of the invention advantageously provides further automation of the printing process.

A method of operating flexographic printing presses having an impression cylinder, printing cylinder carrying a sleeve with a flexographic printing forme or cylinder, uses a sensor adjusting print register of the printing forme or cylinder relative to a further printing forme or cylinder and/or adjusts color density and/or implements color inspection. An image of the sleeve surface with printing forme is recorded by a camera and processed before printing, locating a register mark and/or a color measurement field in terms of x-y positions. A sensor automatically moves for recording the register mark to the y-position of the register mark before adjusting to record the register mark and/or a sensor moves for recording the color measurement field to the y-position of the color measurement field before adjusting to record the color measurement field. Cost-efficient, high-quality industrial printing and further automation is provided.

A printing machine includes a printing roll and an anilox roll or an anilox sleeve for inking a printing forme of the printing roll. The anilox roll or the anilox sleeve is assigned a machine-readable ID. A sensor or a camera detects the ID. A computer retrieves data which is stored in a digital memory in relation to the ID detected from the memory. The computer performs adjustments on the printing machine on the basis of the ID which is read or the retrieved data. A method for adjusting a printing machine is also provided.

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.