Apparatus for orienting magnetic flakes
First Claim
1. An apparatus for orienting magnetic flakes in a fluid carrier printed on a substrate in a printing process, the apparatus comprising:
- a rotatable roller for positioning with an outer surface proximate to the substrate, said roller comprising a cylindrical body encased by a flexible magnetic sheet of a same magnetisable material having an even outer surface forming the outer surface of the rotatable roller, wherein the flexible magnetic sheet comprises one or more selectively magnetized portions surrounded by non-magnetised or differently magnetized portions thereof, said one or more selectively magnetized portions creating a magnetic field emanating from the outer surface of the roller so as to orient the magnetic flakes during the printing process in a selected pattern when the rotatable roller is positioned with an outer surface proximate to the substrate.
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Accused Products
Abstract
A printing apparatus includes a magnetic rotatable roller with a smooth even outer surface for aligning magnetic flakes in a carrier, such as an ink vehicle or a paint vehicle to create optically variable images in a high-speed, linear printing operation. Images can provide security features on high-value documents, such as bank notes. Magnetic flakes in the ink are aligned using magnetic portions of the roller, that can be formed by permanent magnets embedded in a non-magnetic roller body, or selectively magnetized portions of a flexible magnetic cover of the roller. In some embodiments, the roller is assembled for a plurality of interchangeable sections, which can include spinning magnets. Selected orientation of the magnetic pigment flakes can achieve a variety of illusive optical effects that are useful for decorative or security applications.
167 Citations
10 Claims
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1. An apparatus for orienting magnetic flakes in a fluid carrier printed on a substrate in a printing process, the apparatus comprising:
a rotatable roller for positioning with an outer surface proximate to the substrate, said roller comprising a cylindrical body encased by a flexible magnetic sheet of a same magnetisable material having an even outer surface forming the outer surface of the rotatable roller, wherein the flexible magnetic sheet comprises one or more selectively magnetized portions surrounded by non-magnetised or differently magnetized portions thereof, said one or more selectively magnetized portions creating a magnetic field emanating from the outer surface of the roller so as to orient the magnetic flakes during the printing process in a selected pattern when the rotatable roller is positioned with an outer surface proximate to the substrate. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
Specification