The invention relates to the field of the protection of security documents such as for example banknotes and identity documents against counterfeit and illegal reproduction. In particular, the invention relates to optical effect layers (OEL) showing a viewing-angle dependent optical effect, devices and processes for producing said OEL and items carrying said OEL, as well as uses of said optical effect layers as an anti-counterfeit means on documents. The OEL comprises a plurality of non-spherical magnetic or magnetizable particles, which are dispersed in a coating composition comprising a binder material, wherein in at least a loop-shaped area of the OEL at least a part of the plurality of non-spherical magnetic or magnetizable particles are oriented such that their longest axis is substantially parallel to the plane of the OEL, and wherein, in a cross-section perpendicular to the OEL and extending from the center of the central area, the longest axis of the oriented particles present in the loop-shaped area forming the impression of the loop-shaped body follow a tangent of either a negatively curved or a positively curved part of a hypothetical ellipse or circle.

A process for using an inkjet printer to apply translucent inks for producing a pseudo-metallic visual effect on a substrate is disclosed. The process uses a matte printing technique that results in a metallic appearance when applied to various substrates, such as commercial plastic cards. The resulting card product is also disclosed.

An object of the present invention is to provide a thin volume hologram sheet to be embedded sufficiently resistant to a mechanical stress such as a stress including a tensile stress, a shear stress and a compression stress at the time of processing even under a heating condition, a forgery prevention paper and a card using the same. The object is achieved by providing a volume hologram sheet to be embedded comprising a volume hologram layer, and a substrate disposed only on one side surface of the volume hologram layer using an adhesion means, wherein a peeling strength of the volume hologram layer and the substrate is 25 gf/25 mm or more.

An object of the present invention is to provide a thin volume hologram sheet to be embedded sufficiently resistant to a mechanical stress such as a stress including a tensile stress, a shear stress and a compression stress at the time of processing even under a heating condition, a forgery prevention paper and a card using the same. The object is achieved by providing a volume hologram sheet to be embedded comprising a volume hologram layer, and a substrate disposed only on one side surface of the volume hologram layer using an adhesion means, wherein a peeling strength of the volume hologram layer and the substrate is 25 gf/25 mm or more.

An image display that is to be transferred from a support onto a substrate and displays an image including personal information, according to a possible embodiment, includes: a base layer releasably supported by the support, having a light-transmitting property, a first pattern including a hologram and/or diffraction grating and transferred onto a main surface of the base layer, the first pattern displaying a first image including at least a piece of the personal information, the first pattern including dot-shaped portions, each center of the dot-shaped portions being located on a lattice point of a virtual planer lattice; and a second pattern displaying a second image, comprising an ink, and transferred onto the main surface of the base layer. At least a part of the first pattern and at least a part of the second pattern are juxtaposed on a same plane parallel to the main surface of the base layer.

This patent document discloses physical documents including metameric ink pairs. One claim recites a document comprising: a first surface; a second surface, in which the first surface comprises a first set of print structures and a second set of print structures, in which the first set of print structures and the second set of print structures collective convey an encoded signal discernable from optical scan data representing at least a first portion of the first surface, in which the first set of print structures is provided on the first surface with a first ink and the second set of print structures is provided on the first surface with a second, different ink, and in which the first ink and the second, different ink comprise a metameric pair. Of course, other claims and combinations are described as well.

The present disclosure relates to a security structure including a non-opaque, preferably transparent, substrate. The substrate supports metal elements forming a revealing pattern. The metal is thin enough for the metal to be non-opaque. A lacquer is placed at least partially, preferably exactly, on top of the metal elements. The lacquer may be in contact with the metal elements.

A card includes a layer of deformable material embossed with a three dimensional (3-D) pattern. A first layer is in direct contact with and overlies the embossed deformable layer. A second layer is in direct contact with and underlies the embossed deformable layer. The first layer is of conformable material and extends within the embossed pattern for filling, setting and maintaining the embossed pattern in a fixed condition. The second layer is of conformable material and conforms to the embossed pattern set in the deformable layer.

The application discloses apparatus and systems for authenticating physical object, identification documents and security documents. Some such methods and apparatus involve signal encoding or digital watermarking.

The invention includes a method for forming a card with an embedded three dimensional (3-D) image and the resultant card formed by the method. The method includes forming a first assembly which includes a layer of deformable material and an overlying layer of pattern conforming material. An engraved laminating plate is applied to the deformable layer during an engraving and laminating step applied to the first sub-assembly under predetermined pressure and selected temperature conditions for embossing the deformable layer with a well defined and sharp pattern. Then, a second assembly including a pattern conforming layer is laminated with the first assembly to embed and secure the pattern between the two conformable layers.