Abstract: A system (10) includes an intermediate transfer member (ITM) (44) and a substrate conveyor (80). The ITM (44) is configured to receive droplets of one or more printing fluids so as to form an image thereon, and to transfer the image to a target substrate (50). The substrate conveyor (80) is configured to grip and move the target substrate (50) to and from the ITM (44) for transferal of the image, the substrate conveyor (80) includes one or more rotatable elements (110, 200), which are configured to provide mechanical support to the target substrate (50), such that, when the target substrate (50) moves over the one or more rotatable elements (110, 200), at least one of the rotatable elements (110, 200) is configured to rotate in response to a physical contact with the target substrate (50).

Abstract: A device for two-sided printing of sheet-shaped printing substrates includes an impression cylinder on which the printing substrate is guided through more than 360°. As a result of being guided through more than 360°, the second side of the sheet is moved into an effective region of an ink application unit that has already printed a first side of the printing substrate as it was guided on an upstream impression cylinder.

Abstract: Provided is a jacket to be installed on a surface of one of impression cylinders and transport cylinders. The jacket is produced by the following process. Super hard particles, such as ceramic particles, are scattered on a surface of a sheet-shaped base member. A plating layer is then formed on the surface of the base member in a way that a convex and concave profile formed of the super hard particles is left. In the plating layer, fine particles of low surface energy resin are uniformly dispersed.

Abstract: In a printing press and attached onto the transfer cylinders, an anti-marking system that uniformly supports the transport and the release of the wet printed sheet from one station to the next. The anti-marking sheet consists of a two plus layer system, the outer layer being a textured surface and the inner layer being a microcellular material that is both compressible and resilient. The outer textured layer may be treated with either conductive/anti-static layers or an ink repellent layer or both. The two plus layer system is easily attached to both transfer cylinders and tracking/skeleton wheels using any combination of fixtures from Velcro™, magnetic, metallic, and pressure sensitive double sided tape to elastic loops.

Abstract: A method for operating a printing press, which enables a uniform print quality to be achieved during long periods of operation without replacement of the impression cylinder. The printing press comprises several printing units having impression cylinders and a sheet turning device disposed between the printing units. The circumferential surface of the impression cylinder has an ink-repelling surface. The printing press is used to print sheets, until the ink-repelling surface of the circumferential surface of the impression cylinder has been worn away to an extent that the ink-repelling effect is less than a predetermined threshold value, after which a foil, of which the side facing away from the circumferential surface has an ink-repelling surface, is removably placed on the circumferential surface of the impression cylinder.

Abstract: A flexible jacket covering for a printing press transfer cylinder having a low density selvage for attaching one edge of the jacket to a hook and loop attachment strip on the transfer cylinder. The covering is cut from fabric woven on a shuttleless loom. The fabric has a reduced density selvage formed by reducing the density of warp threads in the selvage is no more than the warp thread density in the body of the covering fabric and preferably to about half the warp thread density in the body of the fabric.

Abstract: A cylinder jacket profile for impression cylinders or sheet transfer cylinders has uniformly distributed elevations with an easy-clean layer as a surface coating. The easy-clean layer has a thickness of less than 5 &mgr;m, in particular 1 &mgr;m, and a surface energy of less than 50 mN/m. The cylinder jacket profile has an improved cleaning behavior. A method of producing an easy-clean layer on a cylinder jacket profile is also provided.

Abstract: A rotary printing press transfer cylinder has two or more axially spaced apart discs of a given diameter, each disc having an open minor segment with inwardly disposed edges and a concentric, shaft receiving hub to support the discs for rotation. A flexible plastic sheet, with flanges bent to fit within the inwardly disposed edges, covers the discs to provide a cylindrical shape, and is held under tension by attaching members connected to the flanges. A cushioning, ink repellent jacket is attached over the flexible plastic sheet.

Abstract: The present invention provides a smoothing roller for a printing unit of a rotary printing machine. The smoothing roller is applied to the form cylinder downstream of the ink applicator roller in relation to the direction of rotation of the form cylinder or onto the ink applicator roller itself. The smoothing roller smooths the ink film on the form cylinder or on the ink applicator roller. The outer surface of the smoothing roller has an ink-repelling characteristic. The ink-repelling characteristic is effected by a liquid ink-repelling material such as a separating agent or a dampening medium that is applied to the outer surface of the smoothing roller or by an outer surface of the smoothing roller comprising an ink-repelling material. The two measures for effecting the ink-repellant characteristic of the smoothing roller may also be provided in combination with one another.

Abstract: An ink duct for use with a screen roller which comprises a working doctor blade and a closing doctor blade, wherein the working doctor blade has one or both sides partially or completely coated with an unreleasable coating of a low surface energy substance having a surface energy of 10 to 60 mN/m. This coating prevents disruptive ink deposits from forming on the side of the working doctor blade opposite to the ink retaining portion of the ink duct and reaching the doctored surface of the ink metering roller in an uncontrolled or random manner.

Abstract: A transport drum in a rotary printing press, having a covering for preventing a fresh printed product from being smeared when the printed product is being transported through the press, the covering being secured to the jacket surface of the transport drum and being formed of a carrier material, includes resiliently embodied filamentary support elements secured in the carrier material of the covering, and an ink-repellent material applied to outer ends, respectively, of the support elements.

Abstract: An impression cylinder of a sheet-fed offset printing machine for first form and perfector printing has a multiple diameter and includes a dressing disposed on an outer cylindrical surface thereof for carrying a sheet on a previously printed side thereof, the dressing including a foil having a textured surface for supporting the sheet and having a construction for adjusting to and compensating for inequalities of the impression cylinder, the foil being replaceably fastened on the outer cylindrical surface at least at a sheet carrying region thereof.

Abstract: A film and method for attachment of the film to the surface of a transfer cylinder of an ink printing press. A film base sheet coated with micro-particles of aluminum oxide is releaseably attachable to the outer surface of the cylinder by appropriate adhesives.

Abstract: A ready-made fabric sack with an elastic string around the periphery of the sack opening to be placed over a transfer cylinder in a printing press. When placed over the transfer cylinder, the inherent resiliency of the fabric and string causes the sack to envelop the cylinder to provide a resilient fabric surface which prevents smearing and streaking of wet printed sheets.

Abstract: Foil for covering an impression cylinder of a rotary offset printing press for first-form and perfector printing is formed of a chemically and wear-resistant rigid support layer having good ink transfer behavior and having a structured surface with statistically uniformly distributed convex and concave structural elements thereon, and a microroughness-reducing chromium layer disposed on the rigid support layer and forming a sheet-guiding outer cylindrical surface of the impression cylinder, respective peaks being formed on the convex structural elements for supporting a sheet thereon, each of the convex structural elements having an oval shape with a radius of curvature increasing from the respective peak thereof to a transition into respective concave structural elements adjacent thereto.

Abstract: An apparatus for stretching a cylinder blanket on a sheet transfer cylinder of a sheet-fed printing press includes a tiltable member mounted on the cylinder. A first end of the blanket is first attached to the cylinder in a cylinder groove, the blanket is wrapped around the cylinder, and the second end of the blanket is attached to the tiltable member, while the tiltable member is in an open position. The tiltable member is then closed to stretch the blanket about the cylinder, and locked into the closed position to maintain the blanket about the cylinder.

Abstract: A paper guide wheel for printing presses is formed to include an outer surface eccentric with respect to the axis of rotation of the wheel so as to form an air gap between the outer surface of the wheel and the paper as the paper is drawn thereover during movement through the press. The air gap gradually narrows as the wheel turns, allowing the freshly inked surface of the paper to gently nest against the outer surface at a point removed from the leading edge of the paper. The outer surface has a slightly convex contour in the axial direction to avoid marking of the paper by contact with the axial extremes of the outer surface. Foam material may be provided on the wheel rim to assist in supporting the paper without marking the freshly inked image.

Abstract: An improved sheet-feed drum for guiding and transferring sheets in a rotary printing press is provided with a plurality of round brushes rotatably mounted in closely spaced relation on a plurality of longitudinally extending supporting rods disposed about the periphery of the drum substantially parallel to the drum axis. The brushes are disposed on the support rods over the entire width of the sheets and have bristles made of an ink-repellent material.

Abstract: A metal foil made by electroforming from a master pattern with the interposition of a negative form, and serving as packing for sheet guiding cylinders and/or drums of rotary printing machines, including a substantially planar member having one flat face and an opposite face with a textured surface structure corresponding to an upper side of the master pattern, the upper side of the master patten having been roughened by a jet treatment and coated with a levelling galvano-layer in order to eliminate undercuts, the master pattern per se, and method of manufacture.

Abstract: A paper guide wheel for printing presses is formed to include an outer surface eccentric with respect to the axis of rotation of the wheel so as to form an air gap between the outer surface of the wheel and the paper as the paper is drawn thereover during movement through the press. The air gap gradually narrows as the wheel turns, allowing the freshly inked surface of the paper to gently nest against the outer surface at a point removed from the leading edge of the paper. The outer surface has a slightly convex contour in the axial direction to avoid marking of the paper by contact with the axial extremes of the outer surface. Foam material may be provided on the wheel rim to assist in supporting the paper without marking the freshly inked image.

Abstract: A sheet guiding cylinder of a rotary printing press includes a cylindrical member, at least the outer surface portion of which is formed of chemically resistant, wear-resistant and unyielding material and has a multiplicity of elevated solid surface portions consisting of a distribution of domelike structures of uniform height formed thereon.

Abstract: A transfer cylinder for a printing press having a film of polycarbonate bonded to the surface. The film has a matte surface over which a film of silicone is applied.

Abstract: A rotary printing machine has first and second printing couples for accomplishing recto and verso printing of a web. Each printing couple includes an inking unit, a plate cylinder and an impression cylinder. Each of these impression cylinders may selectively be provided with a soft or a hard cover depending on the type of printing plate secured to the plate cylinder and the type of printing ink used.

Abstract: A skeleton wheel for a printing press has a pair of reel assemblies, one mounted axially along each of the leading and trailing edges of an opening extending the full axial width of the wheel, and to which the ends of an anti-smear fabric web are attached. Each reel assembly includes an axially extending roller which is non-rotatably mounted to the wheel yet permitted limited axial movement.

Abstract: A sheet feed drum for transferring sheets in a rotary printing press wherein the drum other contour is provided with an ink-repellent coating and two circumferentially spaced front and rear drum edges defining a duct therebetween which accommodates a sheet gripper system. The ink-repellent coating supporting a netting-like fabric relatively loosely thereon prevents any smearing of a freshly printed underside of a sheet during sheet feed on the drum while the sheet is engaged by the gripper system. Starting at the front edge of the drum, the outer contour of the drum is constructed in the form of a continuously increasing signal merging into a fixed drum radius whereby the netting-like fabric is contactable by the freshly printed underside of the sheet on the sprial first substantially flatly behind the front edge of the drum and then in any subsequent angle of rotation of the drum without the sheet tangent ever being bent or creased.

Abstract: A skeleton wheel or cylinder for supporting freshly printed sheet material between printing stations or at the delivery station of a printing press is provided with a loosely retained ink repellent fabric covering for supporting and conveying the sheet material without transfer of wet ink from one sheet to a successive sheet and without smearing the ink or indenting the surface of the sheet material. The circumferential surface of the skeleton cylinder is provided with a coating of a fluorocarbon plastic having a fabric base portion bonded to the surface of the cylinder structure. The low friction properties of the coating permit ease of shuffling movement of the fabric covering and the coating structure provides a cushioning effect to prevent smearing or indenting the sheet material by the fabric cover. The improved cylinder is provided with a plurality of retaining plates slidably fitted in axially spaced hub portions of the cylinder which plates are each locked in place by a set screw.

Abstract: A sheet-guiding foil as a sheath for an impression cylinder in rotary offset perfecting presses, one surface of the foil being smooth while the opposite surface thereof is formed with spherical calottes of equal height and of statistically uniform distribution, including a chemically resistant, wear-resistant and rigid backing layer with good ink transfer behavior and a textured surface, and a thin chromium layer applied thereto for evening out microroughness, and the method of production.

Abstract: A feed drum assembly for feeding sheets in succession to the impression cylinder of a lithographic printing press which includes a cylindrical mantle having an axially and circumferentially distributed array of spacers which are spaced radially outward from the surface of the mantle at a constant spacing to define a support for the sheet as it makes a partial turn about the drum. An axially extensive nozzle directs air at high velocity in a direction chordwise of the drum and into the region between the sheet and the mantle. The change in direction of the air as it strikes and tends to follow the curved surface of the mantle creates an inward suction upon the sheet to draw the sheet against the spacers and thereby prevent fluttering as the sheet is transported at high speed. In the preferred embodiment of the invention the spacers are in the form of small, individually rotatable rollers smoothly surfaces with ink repellent synthetic material.

Abstract: A stiff tubular sleeve is externally coated with grit and is telescopically matingly rigidly supported by an idler roll of a continuous printing press. The sleeve and idler roll are detachably keyed together, by an internal clamping mechanism, against both relative axial and angular movements, for rotation in unison as an ink-bearing side of a previously imprinted web of paper or the like runs over the grit coating of the sleeve. Release of the clamping mechanism allows replacement of a sleeve whose grit coating has accumulated excessive ink.

Abstract: A roller wick is positioned to transmit moisture in an uphill direction by capillary action from a roller wick reservoir to an inked paper roller drive means. A thicker relay wick transmits relatively large amounts of fluid from a relay wick reservoir, positioned higher than the roller wick reservoir, to the roller wick reservoir. The relay wick itself is positioned over the roller wick reservoir so that any drippings therefrom are deposited within the roller wick reservoir.