A sheet-fed printing machine comprises at least two sheet-fed printing units. A first sheet-fed printing unit has a first impression cylinder and a second impression cylinder, which cylinders are arranged such that they directly interact with one another and each have an axis of rotation. An axial plane contains these two axes of rotation. A reference plane contains an axis of rotation of this type and has a horizontal surface normal. These two cylinders are arranged such that an intersection angle between the axial plane and the reference plane has a maximum angle of 30°. The first sheet-fed printing unit has at least one plate cylinder, which is in direct contact with or which directly interacts with one of the impression cylinders and which is configured as a numbering plate cylinder or as a flexo cylinder or as a screen printing plate cylinder. A second sheet-fed printing unit has at least one cylinder which is configured as an impression cylinder. The impression cylinder of the first printing unit and the impression cylinder of the second printing unit each have the same circumference.

A sheet-fed printing machine comprises at least two sheet-fed printing units. A first sheet-fed printing unit has a first impression cylinder and a second impression cylinder, which cylinders are arranged such that they directly interact with one another and each have an axis of rotation. An axial plane contains these two axes of rotation. A reference plane contains an axis of rotation of this type and has a horizontal surface normal. These two cylinders are arranged such that an intersection angle between the axial plane and the reference plane has a maximum angle of 30°. The first sheet-fed printing unit has at least one plate cylinder, which is in direct contact with or which directly interacts with one of the impression cylinders and which is configured as a numbering plate cylinder or as a flexo cylinder or as a screen printing plate cylinder. A second sheet-fed printing unit has at least one cylinder which is configured as an impression cylinder. The impression cylinder of the first printing unit and the impression cylinder of the second printing unit each have the same circumference.

Devices are provided for aligning magnetic or magnetizable particles, which particles are contained in a coating that is applied on one side of a substrate, which substrate is in the form of a web or sheet. The device has a magnet cylinder, which is arranged in a transport path of the substrate to be conveyed and, in a region of the outer circumference of the magnet cylinder, the device has a plurality of devices for effecting a magnetic field, or magnet devices for short. Some or all of the magnet devices comprise a magnet which is rotatable by an associated motor. The magnet cylinder is rotatably arranged in frame walls of a frame. At least one transducer for contactless transfer of electrical energy or control signals from the outside is provided in or on the rotating magnet cylinder, which comprises a first transducer part fixed to the frame and a second transducer part fixed to the cylinder during operation.

A sheet-fed printing unit has a first impression cylinder and a second impression cylinder, which are arranged directly and interactingly in contact and which each have an axis of rotation. An axial plane contains the axes of rotation. A reference plane is a plane which contains an axis of rotation of a cylinder of this type and has a horizontal surface normal. These two cylinders are arranged such that an intersection angle between the axial plane and the reference plane is a maximum of 15. A transport path is provided for a transportation of sheets, which transport path has a region for the respective impression cylinder in which there is contact between sheets and a casing surface. This region of the transport path for the respective impression cylinder extends over an angular range of at least 270. A sheet-fed printing machine has a sheet-fed printing unit of this type.

A sheet-fed printing machine comprises two sheet-fed printing units; of which a first is configured as a sheet-fed simultaneous printing unit and has two collector cylinders, which interact with one another and each have an axis of rotation. An axial plane contains the axes of rotation of the collector cylinders. A reference plane contains an axis of rotation of this type and has a horizontal surface normal. An intersection angle between the axial plane and the reference plane is, at a maximum, 45 degrees. A first one of the sheet-fed simultaneous printing units has exactly four plate cylinders, of which exactly two are arranged such that they directly interact with the first collector cylinder and has exactly two others which are arranged such that they directly interact with the second collector cylinder. A second sheet-fed printing unit has at least one impression cylinder and at least one plate cylinder, which is arranged such that it directly interacts with the impression cylinder and which is configured a screen printing plate cylinder, or as a flexo plate cylinder or as a numbering plate cylinder. The two collector cylinders of the first printing unit and the impression cylinder of the second printing unit have the same circumference.

This application relates generally systems and methods for interrupting counterfeiting workflows, and more specifically to methods for adequately concealing aspects of printer configuration, such as number of plates used to print a document or a setup of inks and split fountains. It is therefore possible to obscure the individual plate images and application of ink to those plate images, thereby impeding accurate redrawing of security artwork.

A method of forming an array of microimage elements that vary in their material composition is provided. The method comprises: applying a first region of a layer of a first material to a surface of a first material carrier; applying a second region of a layer of a second material, different from the first material, to a surface of a second material carrier; blending together the first and second regions of the layers of first and second material such that a blended region of the layers of first and second material exhibits a gradual change in relative concentration of the first and second materials along a first direction, the step of blending together the first and second regions of the layers of first and second material comprising bringing a first blending surface into contact with the first material on the surface of the first material carrier and moving the first blending surface relative to the surface of the first material carrier along a direction corresponding to the first direction to spread the layer of first material along the direction corresponding to the first direction, and bringing a second blending surface into contact with the second material on the second material carrier and moving the second blending surface relative to the surface of the second material carrier along a direction corresponding to the first direction to spread the layer of second material along the direction corresponding to the first direction; bringing the blended layers of first and second material in the blended region into contact with a patterned material carrier, the surface of the patterned material carrier defining a pattern corresponding to the array of microimage elements, the patterned material carrier selectively removing the first and second material in at least the blended region in accordance with the pattern; and transferring the blended layers of first and second material defining the array of microimage elements on to a support layer.

There is described a sheet-fed printing press (1000; 1000*) comprising at least two printing units (200; 200.1, 200.2; 200.1*, 200.2*) located one after the other, each printing unit (200; 200.1, 200.2; 200.1*, 200.2*) being adapted to carry out simultaneous recto-verso printing of the sheets (S) and including two printing cylinders (105, 106) cooperating with one an other and forming a printing nip, the two printing cylinders (105, 106) each collecting ink patterns from at least two associated plate cylinders (15A, 15B, 16A, 16B) wherein the two printing cylinders (105, 106) are located one above the other such that the sheets (S) travel laterally through each printing unit (200; 200.1, 200.2; 200.1*, 200.2*) from a first lateral side (201 a; 201 a*) located upstream of the printing nip to a second lateral side (201 b; 201 b*) located downstream of the printing nip, wherein a number of at least two sheet transfer elements (110, 120, 95) is provided downstream of the printing nip of a first one (200.1; 200.1*) and upstream of the printing nip of a second one (200.2; 200.2*) of the at least two printing units (200.1, 200.2; 200.1*, 200.2*) to transfer the sheets (S).

There is described a sheet-fed printing press (1000; 1000*) comprising at least two printing units (200; 200.1, 200.2; 200.1*, 200.2*) located one after the other, each printing unit (200; 200.1, 200.2; 200.1*, 200.2*) being adapted to carry out simultaneous recto-verso printing of the sheets (S) and including two printing cylinders (105, 106) cooperating with one an other and forming a printing nip, the two printing cylinders (105, 106) each collecting ink patterns from at least two associated plate cylinders (15A, 15B, 16A, 16B) wherein the two printing cylinders (105, 106) are located one above the other such that the sheets (S) travel laterally through each printing unit (200; 200.1, 200.2; 200.1*, 200.2*) from a first lateral side (201 a; 201 a*) located upstream of the printing nip to a second lateral side (201 b; 201 b*) located downstream of the printing nip, wherein a number of at least two sheet transfer elements (110, 120, 95) is provided downstream of the printing nip of a first one (200.1; 200.1*) and upstream of the printing nip of a second one (200.2; 200.2*) of the at least two printing units (200.1, 200.2; 200.1*, 200.2*) to transfer the sheets (S).

There is described a printed security element (10; 10*; 10**) comprising a rainbow feature (15; 15*; 15**) exhibiting, at least in part, a gradual transition from a first colour (C1) to a second colour (C2) distinct from the first colour (C1), wherein the rainbow feature (15; 15*; 15**) extends over a colour-gradient area (A) of the printed security element (10; 10*; 10**) where first and second printed patterns (P1, P2) are partly superimposed or juxtaposed, each of the first and second printed patterns (P1, P2) comprising a first, respectively second set of linear or curvilinear elements (20, 30; 20*, 30*), the first and second printed patterns (P1, P2) being printed in register one with the other by means of two distinct printing plates (PP1, PP2) so that the first and second sets of linear or curvilinear elements (20, 30; 20*, 30*) are partly superimposed or juxtaposed in the colour-gradient area (A) and thereby generate the rainbow feature (15; 15*; 15**), the first printed pattern (P1) exhibiting the first colour (C1) and being printed by means of a first printing plate (PP1) and the second printed pattern (P2) exhibiting the second colour (C2) and being printed by means of a second printing plate (PP2), where at least the first or second printed pattern (P1; P2) exhibits, in the colour-gradient area (A), a modulation of line width or line structure such as to cause, when superimposed or juxtaposed with the other printed pattern (P2; P1), a gradual transition from the first colour (C1) to the second colour (C2), wherein, in the colour-gradient area (A), the second printed pattern (P2) is printed on top of the first printed pattern (P1) and wherein the second colour (C2) is darker than the first colour (C1). Also described is a method of producing the aforementioned printed security element.