B42D2035/44

Chiral liquid crystal polymer layer or pattern comprising randomly distributed craters therein
09834031 · 2017-12-05 · ·

Described is a chiral liquid crystal polymer (CLCP) layer or pattern which comprises randomly distributed craters of controlled mean diameter and/or density. The density and/or mean diameter of the craters can be controlled, for example, by adjusting the wetting of a substrate by a CLCP precursor composition, the development time of the precursor composition, and the thickness of the applied precursor composition.

Security devices and methods of manufacture thereof
09804497 · 2017-10-31 · ·

A method of manufacturing a security device including: conveying a substrate web including a photosensitive film along a transport path; exposing the photosensitive film to radiation of a predetermined wavelength through a mask, wherein the mask includes a predetermined pattern of regions which are substantially opaque to radiation of the predetermined wavelength and at least semi-transparent to radiation of the predetermined wavelength, respectively; during the exposure, moving the mask alongside the substrate web along at least a portion of the transport path at substantially the same speed as the substrate web, such that there is substantially no relative movement between the mask and the substrate web; and heating the substrate web including the exposed photosensitive film. In this way, regions of the photosensitive film exposed to the radiation of the predetermined wavelength undergo an increase in optical density such that the photosensitive film displays a reproduction of the predetermined pattern.

Security devices
09731539 · 2017-08-15 · ·

A method and security device, including: a semi-transparent layer exhibiting a first pattern of regions having high optical density and/or raised surface profile relative to layer intervening regions; and a color layer exhibiting a second pattern of elements of at least one color. First and second patterns partially overlap and are configured so the device, appearance varies at different viewing angles. First pattern has color layer following the contours of raised regions. Security device includes: a photosensitive film exhibiting pattern of regions of relatively high and low optical density, the pattern arising from photosensitive film exposure to radiation of a responsive predetermined wavelength from the photosensitive film; and a color layer overlapping the pattern exhibited by photosensitive film, which exhibits increase in optical density upon radiation exposure of a predetermined wavelength and concurrent or subsequent heating. Increases in optical density being due to the bubbles formation within the photosensitive film.

Security element for security papers, value documents or the like
09718297 · 2017-08-01 · ·

A security element for manufacturing value documents, such as banknotes, checks or the like, has an upper side making available several micro images, in particular for a lens magnification arrangement. Each micro image is formed by a micro cavity structure having a multitude of micro cavities disposed side by side, the micro cavities have an extension of 0.5 to 3 μm respectively in a spatial direction disposed parallel to the upper side. The micro cavity structure is optically reflective or highly refractive on its surface, so that on the surface at least partial reflection takes place, and for each micro image micro cavities of at least a first and a second type are present, which differ by an aspect ratio of the micro cavities, whereby each micro image is structured by the at least two different types of micro cavities.

Multi-layer body

The invention relates to a multi-layer body (1) comprising a first layer (13) having a multiplicity of first zones (21), which are respectively separated from one another by one or a plurality of transparent second zones (22). The multi-layer body has a second layer (14) composed of a transparent material, said second layer being arranged below the first layer (13), and a reflection layer (15) arranged below the second layer (14). The second layer (14) has a multiplicity of third zones (23), in each of which a microstructure (17) is impressed into the interface—facing away from the first layer—between the second layer (14) and the reflection layer, which is covered with the reflection layer (15). Each of the microstructures (17) is configured such that it reflects back and/or diffracts back light incident perpendicularly with respect to the plane spanned by the first layer from the direction of the first layer in the region of the respective third zone (23) onto a region of the first layer whose area is smaller than the area of the respective third zone (23) by at least a factor of 10. The microstructures (17) are arranged in accordance with a microstructure grid having a distance between adjacent microstructures in a second spatial direction of less than 300 μm.

Multilayer body

A multilayer body includes a transparent first layer. In the transparent first layer, a multiplicity of microlenses arranged in accordance with a microlens grid are impressed in a first region. Furthermore, the multilayer body includes a second layer, which is arranged below the first layer and in a fixed position with respect to the first layer and has a multiplicity of microimages arranged in accordance with a microimage grid and in each case in an at least regional overlap with one of the microlenses of the microlens grid for the purpose of generating a first optically variable information item. The grid pitches of the microimage grid and of the microlens grid in each case in at least one spatial direction are less than 300 μm.

SECURITY ELEMENT AS WELL AS VALUE DOCUMENT HAVING SUCH A SECURITY ELEMENT
20210070088 · 2021-03-11 ·

A security element for a security paper, value document or the like, having a carrier which has a motif region that includes a visually perceptible motif with a first and a second motif part, wherein the motif region includes a first micro-optic representation arrangement which presents at least two different images in viewing angle-dependent fashion as a first motif part, and a second micro-optic representation arrangement which presents a reflective surface as a second motif part, which surface appears bulged relative to the actual macroscopic spatial form of the second micro-optic representation arrangement.

Process for transferring microstructures to a final substrate

A process for transferring microstructures to a flexible or rigid final substrate that offers advantages in both speed and precision is provided. The inventive process involves subjecting a transfer film in a continuous roll-to-roll process to the following operations: either forming microstructures on, or transferring microstructures to a surface of the transfer film; and then transferring the microstructures from the transfer film onto a surface of the final substrate. The microstructures are single or multi-layer structures that are made up of: voids in a substantially planar surface, the voids optionally filled or coated with another material; raised areas in a substantially planar surface; or combinations thereof.

Security element as well as value document having such a security element

A security element for a security paper, value document or the like, having a carrier which has a motif region that includes a visually perceptible motif with a first and a second motif part, wherein the motif region includes a first micro-optic representation arrangement which presents at least two different images in viewing angle-dependent fashion as a first motif part, and a second micro-optic representation arrangement which presents a reflective surface as a second motif part, which surface appears bulged relative to the actual macroscopic spatial form of the second micro-optic representation arrangement.

PROCESS FOR TRANSFERRING MICROSTRUCTURES TO A FINAL SUBSTRATE

A process for transferring microstructures to a flexible or rigid final substrate that offers advantages in both speed and precision is provided. The inventive process involves subjecting a transfer film in a continuous roll-to-roll process to the following operations: either forming microstructures on, or transferring microstructures to a surface of the transfer film; and then transferring the microstructures from the transfer film onto a surface of the final substrate. The microstructures are single or multi-layer structures that are made up of: voids in a substantially planar surface, the voids optionally filled or coated with another material; raised areas in a substantially planar surface; or combinations thereof.