A method of manufacturing a printing cylinder. The method comprises providing a moulding apparatus comprising a cylindrical moulding vessel defining a moulding cavity (101). The vessel comprises at least one inlet for the ingress of moulding material. The method comprises performing an injection moulding operation comprising: injecting moulding material through the at least one inlet to substantially fill the moulding cavity with moulding material; and effecting hardening of the moulding material within the vessel (102). The method comprises removing the printing cylinder (103). At least part of the injection moulding operation is performed in the presence of an active pressure being applied to the moulding cavity.

A method of manufacturing a printing cylinder. The method comprises providing a moulding apparatus comprising a cylindrical moulding vessel defining a moulding cavity (101). The vessel comprises at least one inlet for the ingress of moulding material. The method comprises performing an injection moulding operation comprising: injecting moulding material through the at least one inlet to substantially fill the moulding cavity with moulding material; and effecting hardening of the moulding material within the vessel (102). The method comprises removing the printing cylinder (103). At least part of the injection moulding operation is performed in the presence of an active pressure being applied to the moulding cavity.

The invention relates to a device for producing security elements (03) on a substrate (02), said device having a first printing couple (21; 22), by means of which substrate (02) being conveyed along a transport path is and/or can be printed with a plurality of first print image elements (12) spaced apart from one another using a first coating medium (11) that contains magnetic particles; a first magnetic cylinder (41), arranged downstream of the first printing couple (21; 22) in the transport path and comprising magnetic elements (43) on its outer circumference; a second magnetic cylinder (42), arranged downstream of the first magnetic cylinder (41) in the transport path and likewise comprising magnetic elements (43) on its outer circumference; and a drying and/or curing device (52), associated with or positioned downstream of the second magnetic cylinder (42) in the transport path, by means of which at least the coating medium (13) of a plurality of second print image elements (14), printed onto the substrate (02) and spaced apart from one another, is and/or can be dried and/or cured at least superficially and/or at least each partially, wherein in the transport path between the first and the second magnetic cylinder (41; 42) a second printing couple (31; 32) is provided, by means of which the substrate (02) is and/or can be printed with the spaced-apart second print image elements (14; 12) using the second coating medium (13) that contains magnetic particles, and wherein a drying and/or curing device (51) positioned upstream of the second printing couple (31; 32) is associated with or positioned downstream of the first magnetic cylinder (41) in the transport path, by means of which device the coating medium (11) containing magnetic particles of the first print image elements (12) printed by the first printing couple (21; 22) is and/or can be dried and/or cured at least superficially and/or at least each partially.

The invention relates to a device for producing security elements (03) on a substrate (02), said device having a first printing couple (21; 22), by means of which substrate (02) being conveyed along a transport path is and/or can be printed with a plurality of first print image elements (12) spaced apart from one another using a first coating medium (11) that contains magnetic particles; a first magnetic cylinder (41), arranged downstream of the first printing couple (21; 22) in the transport path and comprising magnetic elements (43) on its outer circumference; a second magnetic cylinder (42), arranged downstream of the first magnetic cylinder (41) in the transport path and likewise comprising magnetic elements (43) on its outer circumference; and a drying and/or curing device (52), associated with or positioned downstream of the second magnetic cylinder (42) in the transport path, by means of which at least the coating medium (13) of a plurality of second print image elements (14), printed onto the substrate (02) and spaced apart from one another, is and/or can be dried and/or cured at least superficially and/or at least each partially, wherein in the transport path between the first and the second magnetic cylinder (41; 42) a second printing couple (31; 32) is provided, by means of which the substrate (02) is and/or can be printed with the spaced-apart second print image elements (14; 12) using the second coating medium (13) that contains magnetic particles, and wherein a drying and/or curing device (51) positioned upstream of the second printing couple (31; 32) is associated with or positioned downstream of the first magnetic cylinder (41) in the transport path, by means of which device the coating medium (11) containing magnetic particles of the first print image elements (12) printed by the first printing couple (21; 22) is and/or can be dried and/or cured at least superficially and/or at least each partially.

A formative surface having a conductive base covered with a dielectric and oleophobic/hydrophobic surface layer is created with defined pits to grow micro-puddles of a defined volume. The formative surface is brought into close proximity with a charge retentive surface carrying a charge image. Fountain solution vapor nucleates and grows preferentially on the base of the pits as micro-puddle droplets. The puddles are charged and extracted from the surface to provide a fog of charged droplets of narrow volume and charge distribution. The charged droplets are attracted and repelled respectively from the charged and discharged image regions of the charge retentive surface, thus developing the charged image into a fountain solution latent image. The developed latent image is then brought into contact with a transfer member blanket and split, thus creating on the blanket a fountain solution latent image ready for inking.

A formative surface having a conductive base covered with a dielectric and oleophobic/hydrophobic surface layer is created with defined pits to grow micro-puddles of a defined volume. The formative surface is brought into close proximity with a charge retentive surface carrying a charge image. Fountain solution vapor nucleates and grows preferentially on the base of the pits as micro-puddle droplets. The puddles are charged and extracted from the surface to provide a fog of charged droplets of narrow volume and charge distribution. The charged droplets are attracted and repelled respectively from the charged and discharged image regions of the charge retentive surface, thus developing the charged image into a fountain solution latent image. The developed latent image is then brought into contact with a transfer member blanket and split, thus creating on the blanket a fountain solution latent image ready for inking.

Ink-based digital printing systems useful for ink printing include a secondary roller having a rotatable reimageable surface layer configured to receive fountain solution. The fountain solution layer is patterned on the secondary roller and then partially transferred to an imaging blanket, where the fountain solution image is inked. The resulting ink image may be transferred to a print substrate. To achieve a very high-resolution (e.g., 1200-dpi, over 900-dpi) print with these secondary roller configurations, an equivalent very high-resolution fountain solution image needs to be transferred from the secondary roller onto the imaging blanket. To increase the resolution of the image on the secondary roller, examples include a textured surface layer added to the secondary roller for contact angle pinning the fountain solution on the roll. Approaches to introduce a micro-structure onto the surface layer of the secondary roller, and also superoleophobic surface coatings are described.

Ink-based digital printing systems useful for ink printing include a secondary roller having a rotatable reimageable surface layer configured to receive fountain solution. The fountain solution layer is patterned on the secondary roller and then partially transferred to an imaging blanket, where the fountain solution image is inked. The resulting ink image may be transferred to a print substrate. To achieve a very high-resolution (e.g., 1200-dpi, over 900-dpi) print with these secondary roller configurations, an equivalent very high-resolution fountain solution image needs to be transferred from the secondary roller onto the imaging blanket. To increase the resolution of the image on the secondary roller, examples include a textured surface layer added to the secondary roller for contact angle pinning the fountain solution on the roll. Approaches to introduce a micro-structure onto the surface layer of the secondary roller, and also superoleophobic surface coatings are described.

Based on evaporation of fountain solution from a rotating blanket cylinder to create an image that may be inked and printed, a digitally addressable heater array at or just below the blanket surface evaporates deposited fountain solution and forms a fountain solution latent image on the surface. The heater array has controllable heating elements (e.g., field effect transistors, thin film transistors) that provide a transient heat pattern on the surface to evaporate the fountain solution. Heat is generated by current flow in the heating elements, and power developed by the heating circuit is the product of source-drain voltage and current in the channel. Current may be supplied along data lines by an external voltage controlled by digital electronics to provide the desired heat at heating elements addressed by a specific gate line. The heater array may include a current return line that may be a 2-dimensional mesh.

Based on evaporation of fountain solution from a rotating blanket cylinder to create an image that may be inked and printed, a digitally addressable heater array at or just below the blanket surface evaporates deposited fountain solution and forms a fountain solution latent image on the surface. The heater array has controllable heating elements (e.g., field effect transistors, thin film transistors) that provide a transient heat pattern on the surface to evaporate the fountain solution. Heat is generated by current flow in the heating elements, and power developed by the heating circuit is the product of source-drain voltage and current in the channel. Current may be supplied along data lines by an external voltage controlled by digital electronics to provide the desired heat at heating elements addressed by a specific gate line. The heater array may include a current return line that may be a 2-dimensional mesh.