This application claims the priority, under 35 U.S.C. ยง119, of German Patent Application DE 10 2015 213 236.6, filed Jul. 15, 2015; the prior application is herewith incorporated by reference in its entirety.
The present invention relates to a plate for creating holograms or other light-bending or diffractive microstructures on web-shaped or sheet-shaped printing substrates.
The present invention further relates to a manufacturing process for manufacturing a plate for creating holograms or other light-bending or diffractive microstructures on web-shaped or sheet-shaped printing substrates.
Such plates are fixed to a cylinder, for instance a printing press cylinder, to print or emboss the holograms. The holograms may be security features on product packaging.
German Patent Application DE 10 2013 016 117 A1, corresponding to U.S. Patent Application Publication US 2014/0109782, discloses a silicone sheet, known as a silicone shim, that has a microembossing structure for holograms.
It is accordingly an object of the invention to provide a plate suitable for creating partial holograms, also known as spot holograms, and to provide a method suitable for manufacturing such a plate, which overcome the hereinafore-mentioned disadvantages of the heretofore-known devices and methods of this general type.
With the foregoing and other objects in view there is provided, in accordance with the invention, a plate for creating holograms or other light-bending or diffractive microstructures on web-shaped or sheet-shaped printing substrates. The plate includes a relief for a relief printing process. The relief is formed of one or more raised dies and one or more adjacent or neighboring depressions. The relief includes a microrelief disposed exclusively on the dies for printing or embossing the microstructure. The microrelief is non-metallic. Thus the microrelief is formed of a non-metallic material, for instance a cured silicone material, that was a fluid before it was cured.
With the objects of the invention in view, there is also provided a manufacturing process in which a plate for creating holograms or other light-bending or diffractive microstructures on web-shaped or sheet-shaped printing substrates is manufactured. The manufactured plate includes a relief for a relief printing process. The relief is formed of one or more raised dies and one or more adjacent or neighboring depressions. The relief includes a microrelief disposed exclusively on the dies for printing or embossing the microstructure. In the manufacturing process, a primary plate is provided with a negative of the microrelief and the microrelief is created by molding the negative.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a plate for creating holograms and a method for manufacturing the plate, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
Referring now in detail to
The first and second constructions of the plate 7 may be created in a first manufacturing process. In the first manufacturing process, the blank 4 of the plate 7 is provided with the dies 13 in a first step. In a second step, the blank 4 and the primary plate 3 are pressed together, trapping the fluid 6 between the blank 4 and the primary plate 3 and in the process, applying at least a part of the fluid 6 to the blank 4 and molding the negative 17 exclusively in the fluid 6 applied to the dies 13 of the relief 12. In the first step, the blank 4 of the plate 7 is provided with the dies 13 by ablating material in the regions of the depressions 14. The ablation of the material may be achieved by cutting, laser treatment, or etching. The second step is carried out in the roller unit shown in
The manufacturing of the first and second construction alternatives of the plate 7 may be achieved in a second manufacturing process. In this process, in a first step, the blank 4 of the plate 7 and the primary plate 3 are pressed together, trapping the fluid 6 between the blank 4 and the primary plate 3 and, in this process, applying at least a part of the fluid 6 to the entire surface of the blank 4 and molding the negative 17 in the applied fluid 6 and, in a second step, the blank 4 is provided with the dies 13. The first step is carried out in the roller unit shown in
The manufacturing of the first and second construction alternatives of the plate 7 may be achieved in a third manufacturing process. In this process, the blank 4 of the plate 7 and the primary plate 3 are pressed together, trapping the fluid 6 and the stencil or mask 5 between the blank 4 and the primary plate 3 when the negative 17 is formed. There are three options for placement of the stencil or mask 5.
In accordance with the first option, the stencil or mask 5 is connected to the primary plate 3 before and during the pressing operation and is removed from the primary plate 3 after the pressing operation. The stencil or mask 5 may be formed by a varnish that is applied to the primary plate 3 and cured thereon and is washed off the primary plate 3 once the plate 7 is finished, allowing the primary plate 3 to be re-coated with a print job-specific stencil or mask of varnish in order to create another plate for a different print job. Alternatively, the stencil or mask 5 may be formed by a self-adhesive film that adheres to the primary plate 3 and is pulled off the primary plate 3 once the plate 7 is finished, subsequently allowing another self-adhesive film to be applied to the primary plate 3 as a stencil or mask 5 in order to create another plate for a different print job.
In accordance with the second option, the stencil or mask 5 is connected to the blank 4 before and during the pressing operation and is removed from the blank 4 after the pressing operation. The stencil or mask 5 may be formed by a varnish that is applied to the blank 4 and cured thereon and is washed off the blank 4 once the plate 7 is finished. Alternatively, the stencil or mask 5 may be formed by a self-adhesive film that adheres to the blank 4 and is pulled off the blank 4 once the plate 7 is finished.
In accordance with the third option, the stencil or mask 5 is separate from both the primary plate 3 and the blank. The stencil or mask 5 may be formed by a film that is loosely placed between the primary plate 3 and the blank 4 to form the stack (see
In all three options, the stencil or mask 5 has a thickness corresponding to the height of the structuring layer 11 and one or more recesses having outlines which correspond to those of the dies 13. In the pressing operation, at least a part of the fluid 6 is displaced into the recesses of the stencil or mask 5, where it is applied to the blank 4.
Number | Date | Country | Kind |
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102015213236.6 | Jul 2015 | DE | national |