De La Rue International Limited

Opsec Security Group, Inc.

Dlr Newco Limited

Hueck Folien Gesellschaft M.b.h.

Brian William Holmes

Lawrence George Commander

Kenneth John Drinkwater

John Godfrey

Maria King

Robert Whiteman

Ralph Kay

Roland Isherwood

Christopher John Eastell

David Allen Stone

Frederic Fournier

Malcolm Robert Murray Knight

Adam Lister

Paul Howland

John Martin Haslop

John David Wiltshire

Michael Fickes

Michael Levin

Fred Fournier

Mark Deakes

Ian Cornes

John O'Malley

Navin Suyal

Richard Ward

David Stone

A method of forming a security device includes: a holographic image layer, diffusion element, and barrier layer. A region of the barrier layer includes a heat-transformable material. The method further includes selectively applying heat at a plurality of positions within the region of the barrier layer, in accordance with a predetermined pattern, so as to modify the heat-transformable material such that the region of the barrier layer is selectively rendered passable to the diffusible substance at each of the plurality of positions, thereby permitting diffusion of the diffusible substance between the regions of the diffusion element and the holographic image layer such that, at a plurality of positions within the region of the holographic image layer and corresponding to the predetermined pattern, the volume hologram is dimensionally modified so as to become viewable in a second observable colour, different from the first observable colour.

Method of forming a security device

An optical device is provided that exhibits a variable optical effect upon illumination. The optical device has a diffractive structure comprising: a portion of a first kinoform diffractive structure that encodes a first image, arranged to form a first diffractive region () of the diffractive structure; and a portion of a second kinoform diffractive structure that encodes a second image, arranged to form a second diffractive region () of the diffractive structure; wherein the first diffractive region and the second diffractive region are laterally separate; and each of the first diffractive region and the second diffractive region are discernible by the naked human eye. Methods of manufacture of such optical devices are also disclosed.

Optical devices and methods of manufacture thereof

A security device includes an array of reflective elements including at least first and second sets of reflective elements, which are regularly or irregularly interlaced along at least a first interlacing direction across a first area of the security device. A non-dispersive colour-generating structure is in the surface of first and/or second sets of reflective elements. The first set of reflective elements is configured to collectively exhibit a first image across the first area of the security device to a viewer within a first viewing zone and direct incident light convergently and/or divergently towards this zone. The second set of reflective elements is configured to collectively exhibit a second image across the first area of the security device to the viewer within a second viewing zone. The structure is modulated across the first and/or second sets of reflective elements such that the first and/or second images include multiple colours.

Security devices and methods of manufacture

A security element including: a first layer having a first surface; an array of image regions across the surface, each region including at least first and second sub-regions; a first diffractive optically variable effect generating structure in or on the surface across the first sub-regions; and a second diffractive optically variable effect generating structure in or on the surface across the second sub-regions; wherein the surface is arranged so each first sub-region has a first average inclination and each second sub-region has a second average inclination different from the first, wherein the first structure and inclination provide that the first effect is exhibited across the first sub-regions at least at a first viewing angle and the second structure and inclination provide that the second effect is exhibited across the second sub-regions at least at a second viewing angle different from the first. Also, a method of manufacturing the security element.

Security elements and methods of manufacture thereof

A security device includes a diffractive structure, including grating elements and having a first area, the grating elements within a region have a constant pitch or spacing; the first area regions pitches or spacings increase from one region to the next between a first region having a grating element pitch or spacing of less than or equal to 0.6 microns and an end region having a grating element pitch or spacing of greater than or equal to 5 microns; upon illumination and viewing along a first viewing direction substantially orthogonal to the first axis, the device exhibits a first optical effect in that at least one region exhibits a diffractive colour; each region has at least first and second sub-regions having different grating element orientations within the plane of the device such that the first optical effect is exhibited at more than one angle of tilt about the second axis.

Security device and method of manufacture thereof

A method of forming a security device includes selectively providing a high refractive index (HRI) layer to a first outwardly facing surface of a security device substrate, the HRI layer having a substantially transparent host material and particles having a dimension along at least one axis less than 200 nm, such that they are substantially non-scattering to visible light and the HRI layer is substantially transparent to visible light, and wherein; the particles have a refractive index of at least 1.8 and are present within the host material in a proportion such that the resultant refractive index of the HRI layer is at least 1.6. A corresponding security device, as well as security articles and security documents, are also disclosed.

A security element including: a first layer having a first surface; an array of image regions across the first surface arranged along at least a second direction, each region including at least a first image sub-region having an average inclination defining an angle, relative to a plane of the security element, about an image region axis extending along a first direction; a diffractive optically variable effect generating structure provided in or on the first surface across the first image sub-regions, the structure including diffractive elements that extend along a direction within 45&#xb0; of the first direction, wherein the structure is provided across the first image sub-regions and spatially arranged and/or modulated across the first image sub-regions in accordance with a first image so the first image is displayed by the first image sub-regions in combination at least at a first viewing angle. Also, a method of manufacturing the security element.

A method of manufacturing an image element array for a security device is disclosed. The method comprises: (a) providing a metallised substrate web comprising a substrate having a first metal layer thereon on a first surface of the substrate, the first metal layer being soluble in a first etchant substance; (b) applying a first photosensitive resist layer to the first metal layer; (c) exposing the first photosensitive resist layer to radiation of a wavelength to which the resist layer is responsive through a patterned mask, by conveying the substrate web along a transport path and, during the exposure, moving the patterned 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, wherein the patterned mask comprises first pattern elements in which the mask is substantially opaque to the radiation and second pattern elements in which the mask is substantially transparent to the radiation, whereupon the exposed second pattern elements of the first photosensitive resist layer react resulting in increased solubility by a second etchant substance, the non-exposed first pattern elements remaining relatively insoluble by the second etchant substance; and (d) applying the first and second etchant substances to the substrate web whereupon the second pattern elements of both the first resist layer and the first metal layer are dissolved, the remaining first pattern elements of the first metal layer forming an image element array.

Security devices and methods of manufacture thereof

A method of manufacturing a security document, including: providing a polymer substrate having first and second surfaces; and: applying an array of focussing elements to the first surface of the polymer substrate across a first region; forming an image array by: providing a die form having a surface including an arrangement of raised areas and recessed areas defining the pattern; applying a first curable material to the surface of the die form so it substantially fills the recessed areas; bringing a pattern support layer in contact with the surface of the die form so it covers the recessed areas; separating the pattern support layer from the surface of the die form so the first curable material in the recessed areas is removed from the recessed areas and retained on the pattern support layer; and at least partly curing the first curable material in one or more curing steps.

Methods of manufacturing security documents and security devices

A security device is disclosed, comprising an array of focussing elements with regular periodicity in at least a first direction, each focusing element having an optical footprint of which different portions will be directed to the viewer in dependence on the viewing angle; and an array of image elements with regular periodicity in at least the first direction overlapping the array of focusing structures, the image elements representing portions of at least two respective images, and at least one image element from each respective image being located in the optical footprint of each focusing structure. The security device includes a first region and a second region which is laterally offset from the first, the image elements in the first region being laterally shifted in at least the first direction relative to the image elements in the second region such that, at a first viewing angle, in the first region of the device the focussing structures direct image elements corresponding to a first image to the viewer such that the first image is displayed across the first region of the device, and simultaneously, in the second region of the device, the focussing structures direct image elements corresponding to a second image to the viewer such that the second image is displayed across the second region of the device, and at a second viewing angle the second image is displayed across the first region of the device and simultaneously the first image is displayed across the second region of the device. The security device further comprises a colour filter located in use between the image elements and the viewer, the colour filter overlapping at least part of the array of focussing elements and the array of image elements, and having a first colour in the first region of the device and a different colour in the second region of the device such that the colour appearance of the first and second images is different in the respective first and second regions of the device.

Security devices

A method of manufacturing a security device is provided. The method comprises providing a substrate, the substrate having opposing first and second surfaces and a relief structure formed in the first surface of the substrate. A reflection enhancing layer is applied over the first surface of the substrate such that the reflection enhancing layer at least partially overlaps the relief structure and such that a first region of the first surface of the substrate does not have the reflection enhancing layer. An absorber layer is applied over the reflection enhancing layer such that the absorber layer at least partially overlaps the reflection enhancing layer and the relief structure where the reflection enhancing layer and the relief structure overlap each other, and such that the absorber layer at least partially overlaps the first region of the first surface of the substrate. An optical spacer layer is applied over the absorber layer such that the optical spacer layer at least partially overlaps the absorber layer, reflection enhancing layer and the relief structure where the absorber layer, reflection enhancing layer and the relief structure overlap each other, and such that the optical spacer layer at least partially overlaps the absorber layer and the first region where the absorber layer and the first region overlap each other. A reflector layer, formed of an at least partially reflective material, is applied over the optical spacer layer such that the reflector layer at least partially overlaps the optical spacer layer, the absorber layer, the reflection enhancing layer and the relief structure where the optical spacer layer, the absorber layer, the reflection enhancing layer and the relief structure overlap each other, and such that the reflector layer at least partially overlaps the optical spacer layer, the absorber layer and the first region where the optical spacer layer, the absorber layer and the first region overlap each other. The reflection enhancing layer and the absorber layer are formed of the same material. The absorber layer, the optical spacer layer and the reflector layer, together, form a colour-shifting structure. The reflection enhancing layer and the absorber layer, together, are substantially opaque or transmit less than 40% of incident light, preferably less than 20% of incident light.

A diffractive security device is disclosed including at least a first diffractive structure defined in a carrier layer. The first diffractive structure is an on-axis diffractive zone plate structure of a continuously curved surface configured such that when the device is illuminated by on-axis light a first diffraction pattern generated by the first diffractive structure can be viewed from at least a first side of the device at substantially all viewing angles, the first diffraction pattern exhibiting a reference point or reference line relative to which other features of the first diffraction pattern appear to move when the viewing angle is changed.

Diffractive security device and method of manufacture thereof

A diffractive security device is disclosed, including first and second diffractive structures defined in a carrier layer. The first diffractive structure is a diffractive zone plate structure of a continuously curved surface configured such that when the device is illuminated by on-axis light, a first diffraction pattern generated by the first diffractive structure can be viewed from at least a first side of the device at substantially all viewing angles, the first diffraction pattern exhibiting a reference point or reference line relative to which other features of the first diffraction pattern appear to move when the viewing angle is changed. The second diffractive structure is an off-axis diffractive structure configured such that when the device is illuminated by on-axis light a second diffraction pattern generated by the second diffractive structure can be viewed from at least the first side of the device at at least some off-axis viewing angles.

A security device is disclosed, comprising forming an array of focussing elements on first region of first surface of focussing element support layer, applying a pedestal layer comprising one transparent material onto first region of first surface of focussing element support layer applying transparent curable material to the pedestal layer or a casting tool carrying surface relief corresponding to focussing elements, over first region forming transparent curable material(s) with the casting tool bringing first surface of focussing element support layer against the casting tool that transparent curable material between the surface relief and the pedestal layer, across first region; and curing transparent curable material(s) on the pedestal layer to retain surface relief in first region; wherein focal length of focussing elements focal plane lies on first surface of focussing element support layer, or beyond first surface of focussing element support layer relative to the location of array of focussing elements.

A method of applying a pattern formed of two different materials to a pattern support layer includes: providing a die form having a surface with recesses defining the pattern; applying a first curable material to a surface first region, received in some of the first region recesses and partially filling a first region recess set; applying a second curable material to some of the surface first region, the second curable material at least partially fills the first set of the first region recesses; contacting a pattern support layer with the die form surface to cover the recesses containing both the first and second curable materials; separating the pattern support layer from the die form surface, the first and second curable materials in the covered recesses removed therefrom and retained on the pattern support layer; and curing the first and second curable materials during and/or after the second and third steps.

Growing community of inventors

Fleet, United Kingdom

Brian William Holmes