The present invention relates to the field of and processes and printing apparatuses for producing optical effect layers (OEL) comprising magnetically oriented platelet-shaped magnetic or magnetizable pigment particles on a substrate. In particular, the present invention relates to processes using printing apparatuses comprising a first magnetic-field-generating device mounted on a transferring device (TD) and a static second magnetic-field-generating device for producing said OELs as anti-counterfeit means on security documents or security articles or for decorative purposes.

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.

There is disclosed a method of printing onto the surface of a substrate, which method comprises i) coating a donor surface with a monolayer of particles, ii) treating the substrate surface to render at least selected regions tacky, and iii) contacting the substrate surface with the donor surface to cause particles to transfer from the donor surface only to the tacky regions of the substrate surface. After printing on a substrate, the donor surface returns to the coating station where the continuity of the monolayer is restored by recovering with fresh particles the regions of the donor surface exposed by the transfer of particles to the substrate.

In some examples, a machine for generating optically variable image elements on a substrate includes a printing substrate infeed and a printing unit including a printing mechanism by which a substrate guided on a transport path is printed with a coating agent containing magnetic or magnetizable particles. A device for aligning the magnetic or magnetizable particles includes a first alignment device in the transport path and a further alignment device arranged upstream therefrom. During normal operation, the further alignment device is fixed to a frame at the transport path. The further alignment device includes a plurality of magnets that are spaced apart from one another transversely to the transport direction and, during operation, remain stationary. The number of magnets included in the further alignment device correspond to a number of columns of image-producing print motifs or groups of image-producing print motifs around a circumference of a forme cylinder.

A device is provided for aligning magnetic or magnetizable particles, which are contained in a coating that is applied to a first side of a web-type or a sheet-type substrate. An application device is arranged in the transport path of the substrate, by the use of which, the coating is applied or is applicable to the first side of the substrate, in at least one application site. A first cylinder, which is embodied as a magnetic cylinder, is arranged in the transport path of the substrate to be transported downstream of the application device and comprises a plurality of elements creating a magnetic field in the region of the outer periphery of the first cylinder. Another cylinder, which is embodied as a magnetic cylinder, is arranged in the transport path of the substrate to be transported and comprises a plurality of elements creating a magnetic field in the region of the outer periphery of that cylinder. A drying device or an hardening device is arranged on the transport path between a site of a winding-on of the substrate on the first cylinder and a site of a winding-on of the other cylinder. The first cylinder, which is embodied as the magnetic cylinder, is arranged in the transport path of the substrate to be transported on the second side thereof. The drying or the hardening device is oriented in the transport path of the substrate to be transported on the first side thereof.

The invention relates to a method and an apparatus for cold-stamping onto a three-dimensional object. In a first step, an adhesive is applied to the object at a first workstation. In a second step, a transfer film is pressed onto the object by a pressing device at a second workstation. At the same time, the adhesive is cured at the second workstation. As a result, the decorative material of the transfer film adheres to the object at the positions on the object which are provided with adhesive. If, following this, the transfer film is removed from the three-dimensional object after being pressed on, the decorative material remains on the object at the desired positions. At the positions at which in the first step no adhesive has been applied to the object, the decorative material does not adhere to the object but rather remains on the carrier film of the transfer film.

A cylinder is usable, in particular, for aligning magnetic of magnetizable particles, which are contained in a coating medium that is applied to a first side of a web-like or a sheet-like substrate, which cylinder, in the region of its outer circumference, has a plurality of elements effecting a magnetic field, magnetic elements for short. The magnetic elements are arranged in or on a plurality of ring elements that are spaced axially apart from one another and that are positionable in the axial direction on a shaft, in or on which ring elements, in turn, a plurality of magnetic elements are respectively arranged one after the other in the circumferential direction. At least two adjacent ring elements, each have a covering element, forming a part of the cylindrical lateral surface of the cylinder and extending in the circumferential direction, at least over the circumferential region populated with magnetic elements. The covering elements of two ring elements adjacent to each other have, on their sides facing each other in the axial direction, a plurality of projections alternating in the circumferential direction with recesses and offset in a circumferential direction in such a way that, during a relative movement of the two ring elements towards each other, the projections on the covering element of one ring element engage, in the manner of teeth, in corresponding recesses of the other ring element, and, as seen in the circumferential direction, can overlap. A security paper printing machine, having such a cylinder, is also disclosed.

An apparatus is disclosed for coating a surface that is movable relative to the apparatus with a layer of metallic particles or particles having a metal-like appearance and reflectivity, the particles adhering more strongly to the surface than to one another. The apparatus comprises at least one spray head for directly or indirectly applying to the surface a fluid stream within which the particles are suspended, a housing surrounding the spray head(s) and defining an interior plenum for confining the fluid stream, the housing having a rim adjacent the surface that is configured to prevent egress of particles from a sealing gap defined between the rim of the housing and the surface to be coated, and a suction source connected to the housing to extract from the plenum the sprayed fluid and particles suspended in the sprayed fluid. In operation, the suction source extracts substantially all particles that are not in direct contact with the surface, so as to leave only a substantially single particle layer adhering to the surface on exiting the apparatus.

The present invention relates to the field of and processes and printing apparatuses for producing optical effect layers (OEL) comprising magnetically oriented platelet-shaped magnetic or magnetizable pigment particles on a substrate. In particular, the present invention relates to processes using printing apparatuses comprising a first magnetic-field-generating device mounted on a transferring device (TD) and a static second magnetic-field-generating device for producing said OELs as anti-counterfeit means on security documents or security articles or for decorative purposes.

A system for forming a security pattern by magnetic and optical fields includes: a printing substrate having an inducible ink pattern printed on its surface; and at least one set of security pattern forming units through which the printing substrate passes sequentially. Each set of security pattern forming units includes: a magnetic field and a light source each acting on a surface of the printing substrate, such that after the printing substrate passes through the security pattern forming unit, an inducible ink pattern on the surface thereof exhibits the effect of the dual function of the optical field and the magnetic field.