EP1152907A1 - Security document including a nanoparticle-based authentication device - Google Patents
Security document including a nanoparticle-based authentication deviceInfo
- Publication number
- EP1152907A1 EP1152907A1 EP99950399A EP99950399A EP1152907A1 EP 1152907 A1 EP1152907 A1 EP 1152907A1 EP 99950399 A EP99950399 A EP 99950399A EP 99950399 A EP99950399 A EP 99950399A EP 1152907 A1 EP1152907 A1 EP 1152907A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- particles
- security document
- substrate
- document according
- producing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C59/00—Surface shaping of articles, e.g. embossing; Apparatus therefor
- B29C59/02—Surface shaping of articles, e.g. embossing; Apparatus therefor by mechanical means, e.g. pressing
- B29C59/022—Surface shaping of articles, e.g. embossing; Apparatus therefor by mechanical means, e.g. pressing characterised by the disposition or the configuration, e.g. dimensions, of the embossments or the shaping tools therefor
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B42—BOOKBINDING; ALBUMS; FILES; SPECIAL PRINTED MATTER
- B42D—BOOKS; BOOK COVERS; LOOSE LEAVES; PRINTED MATTER CHARACTERISED BY IDENTIFICATION OR SECURITY FEATURES; PRINTED MATTER OF SPECIAL FORMAT OR STYLE NOT OTHERWISE PROVIDED FOR; DEVICES FOR USE THEREWITH AND NOT OTHERWISE PROVIDED FOR; MOVABLE-STRIP WRITING OR READING APPARATUS
- B42D25/00—Information-bearing cards or sheet-like structures characterised by identification or security features; Manufacture thereof
- B42D25/20—Information-bearing cards or sheet-like structures characterised by identification or security features; Manufacture thereof characterised by a particular use or purpose
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
- B29C70/58—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising fillers only, e.g. particles, powder, beads, flakes, spheres
- B29C70/585—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising fillers only, e.g. particles, powder, beads, flakes, spheres incorporation of light reflecting filler, e.g. lamellae to obtain pearlescent effet
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
- B29C70/58—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising fillers only, e.g. particles, powder, beads, flakes, spheres
- B29C70/60—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising fillers only, e.g. particles, powder, beads, flakes, spheres comprising a combination of distinct filler types incorporated in matrix material, forming one or more layers, and with or without non-filled layers
- B29C70/603—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising fillers only, e.g. particles, powder, beads, flakes, spheres comprising a combination of distinct filler types incorporated in matrix material, forming one or more layers, and with or without non-filled layers and with one or more layers of pure plastics material, e.g. foam layers
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
- B29C70/58—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising fillers only, e.g. particles, powder, beads, flakes, spheres
- B29C70/60—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising fillers only, e.g. particles, powder, beads, flakes, spheres comprising a combination of distinct filler types incorporated in matrix material, forming one or more layers, and with or without non-filled layers
- B29C70/606—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising fillers only, e.g. particles, powder, beads, flakes, spheres comprising a combination of distinct filler types incorporated in matrix material, forming one or more layers, and with or without non-filled layers and with one or more layers of non-plastics material or non-specified material, e.g. supports
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
- B29C70/58—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising fillers only, e.g. particles, powder, beads, flakes, spheres
- B29C70/62—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising fillers only, e.g. particles, powder, beads, flakes, spheres the filler being oriented during moulding
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B27/00—Layered products comprising a layer of synthetic resin
- B32B27/06—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material
- B32B27/08—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B42—BOOKBINDING; ALBUMS; FILES; SPECIAL PRINTED MATTER
- B42D—BOOKS; BOOK COVERS; LOOSE LEAVES; PRINTED MATTER CHARACTERISED BY IDENTIFICATION OR SECURITY FEATURES; PRINTED MATTER OF SPECIAL FORMAT OR STYLE NOT OTHERWISE PROVIDED FOR; DEVICES FOR USE THEREWITH AND NOT OTHERWISE PROVIDED FOR; MOVABLE-STRIP WRITING OR READING APPARATUS
- B42D25/00—Information-bearing cards or sheet-like structures characterised by identification or security features; Manufacture thereof
- B42D25/20—Information-bearing cards or sheet-like structures characterised by identification or security features; Manufacture thereof characterised by a particular use or purpose
- B42D25/29—Securities; Bank notes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C59/00—Surface shaping of articles, e.g. embossing; Apparatus therefor
- B29C59/02—Surface shaping of articles, e.g. embossing; Apparatus therefor by mechanical means, e.g. pressing
-
- B42D2033/20—
-
- B42D2035/24—
-
- B42D2035/34—
Definitions
- the present invention relates to security documents such as banknotes, credit cards and other documents of value, and is particularly concerned with providing a security document with an authentication device for verifying the authenticity of the security document.
- the invention is also concerned with a method of producing such security documents.
- An aim of the present invention is to provide an authentication device for incorporation in a security document which acts to effectively circumvent counterfeiting of the security document.
- one aspect of the present invention provides a security document comprising a sheet-like substrate having one or more layers containing particles for forming an authentication device in a first location on the security document, the particles having at least a first dimension in the range of 1 to 200 nanometers.
- the particles may be substantially spherical.
- the particles may be elongated.
- the particles may be a series of spherical particles concatenated together, in the form of "beads-over-string".
- at least a first group of the particles may be aligned so that their longitudinal axes are substantially parallel.
- the longitudinal axis of the first group of particles may extend in a first direction at an angle to the plane of the security document.
- a second group of the particles may be aligned so that their longitudinal axes extends in a second direction at an angle to the plane of the security document, the first and second directions being non-co-linear.
- the first group of particles may be arranged so as to polarize incident light waves.
- the security document may include, at a second location, a polarizing analyzer for interaction with the light polarizer at the first location.
- the particles may be laterally spaced from each other so as to form at least a first diffraction grating at the first location.
- the lateral spacing may be achieved by coating each particle with a transparent material of controllable thickness, such as silica.
- the particles may be selected from materials which reflect incident light waves. Alternatively, the particles may act to fluoresce or luminesce light waves therefrom.
- the particles may be selected from materials to reflect incident sound or acoustic waves or from materials that absorb energy (light or sound) and subsequently re-emit this energy acoustically.
- the particles may be made from material which is orientable in an electric, magnetic or electromagnetic field. In this way, alignment of the particles may be affected by selective application of that specified field to at least the first group of particles.
- Another aspect of the present invention provides a method of producing a security document, comprising the steps of:
- the external field may be for example an electric, magnetic, electromagnetic, mechanically induced stress field.
- a further aspect of the present invention provides a method for producing a security feature for use in a security document, comprising the steps of:
- the particles may be deposited by an electro-deposition process.
- the outer layer may be made from a polymer-based material.
- the pores may be formed by orienting the substrate so that its plane is at an angle to the beam of an energy source, exposing the substrate to the energy source beams such that pores are formed in an outer layer of the substrate, the longitudinal axis of the pores being substantially aligned with the direction of the energy source beam.
- the die may be heated so that an outer layer of the substrate is melted thereby to facilitate the transfer of the particles from the transfer film into the substrate.
- the die may be an embossing die and may be adapted to form a saw-tooth or like profile in the surface of the substrate, in order to enable the positioning of the particles in the outer layer of the substrate, whereby the longitudinal axis of the particles is at an angle to the plane of the security document.
- a further aspect of the invention provides a method of producing s security document, comprising the steps of:
- Figure 1 is a cross-sectional side view of a first embodiment of a security document according to the present invention
- Figure 2 is a cross-sectional side view of a second embodiment of a security document according to the present invention
- Figure 3 is a perspective view of the security document of Figure 2;
- Figure 4 is a diagram showing the spectral absorption of particles for use in a security document according to the present invention;
- Figure 5 is a schematic diagram showing the orientation of the particles used in the security document of Figure 2;
- Figures 6 and 7 are cross-sectional side views of a third embodiment of a security document according to the present invention.
- Figures 8 and 9 are schematic representations of portions of the security document of Figures 6 and 7;
- Figure 10 is a schematic plan view showing a lined particle suitable for use in a security document according to the present invention.
- Figure 11 is a schematic plan view of particles encapsulated in a clear transparent material for use in a security document according to the present invention.
- Figure 12 is a cross-sectional side view of a fourth embodiment of a security document according to the present invention.
- Figure 13 is a cross-sectional side view of a fifth embodiment of a security document according to the present invention
- Figure 14 is a schematic diagram showing a first method of locating particles in a substrate so as to form a security document according to the present invention.
- Figure 15 is a schematic diagram showing a second method for enabling the location of particles in a substrate so as to form a security document according to the present invention.
- a banknote 1 comprising a sheet-like substrate 2 preferably of plastics material and having first and second opposing surfaces 3 and 4.
- Various indicia may be formed on at least one of the first and second opposing surfaces 7 and 8, such as drawings, writing and other designs well known to manufacturers and users of banknotes.
- the substrate is preferably a composite made from at least biaxially oriented polymeric film 5 which is coated on both sides with an opacifying pigmentry coating 6 and 7 comprising a major portion of pigment in a minor portion of cross-linked polymeric binder.
- a transparent protective coating (not shown) is preferably applied to both sides of the banknote 1 in order to protect it from wear.
- the transparent protective layer may include silica or like particles so as to improve the adherence of the banknote 1 when handled by a user.
- the substrate 2 includes copolymer outer coatings 8 and 9 of the biaxially oriented polymeric film 5.
- An authentication device 10 is formed at a first location on the banknote 1 by the inclusion of nanoparticles in at least a portion of the copolymer outer coating 8. These nanoparticles have at least a first dimension in the range of 1 to 200 nanometers, and, when included in a security document, provide a number of features suitable for use as an authentication device, as will be explained below.
- the opacification layer 6 of the banknote 1 does not extend over the entire surface 3 of the substrate 2, but leaves a portion of the substrate 2 uncovered in the vicinity of the authentication device 10.
- This embodiment of the authentication device 10 takes advantage of particular optical effects of the nanoparticles included in the copolymer outer layer 8 or otherwise visible by a user.
- nanoparticles made from gold or other material which scatters and absorbs incident light waves are used in the authentication device 10. Nanoparticles of this type have been observed to exhibit isotropic absorption of incident light waves, their absorption spectrum being a function of both their aspect ratio, that is to say the ratio of their length to width, and their orientation.
- nanorods, nanoellipsoids or other elongated nanoparticles may be used in order to alter the colour observed by a user both under specular reflection and by diffuse reflectance of light on the surface of the authentication device 10.
- the same nanoparticles have also been observed to exhibit a colour shift when viewed in transmission versus reflection.
- Figure 2 shows a banknote 20 which takes advantage of this property.
- the same substrate 2, including the biaxially oriented polymeric film 5 and copolymer outer coatings 8 and 9 are used.
- the opacifying layers 6 and 7 do not entirely cover the outer surfaces 3 and 4 of the substrate, but leave open a region W enabling the transmission of light through the substrate 2.
- a colour difference is observed by a user depending upon whether light from a source 21 is viewed in reflection, at position 22, or in transmission, at position 23.
- a variation in the colour observed by a user may also be achieved by the alignment of elongate nanoparticles in the authentication device 10. Alignment of at least a first group of the particles so that their longitudinal axes are substantially parallel results in not only a colour variation depending upon the angle ⁇ at which the banknote 20 is tilted, but which is also dependent upon an angle ⁇ at which the banknote is rotated whilst being maintained in substantially the same plane.
- the longitudinal axis of a first group of elongate nanoparticles are arranged to extend in a first direction at an angle to the plane of the security document, a noted colour variation depending upon the angle of rotation ⁇ of the banknote 20 is observed.
- the group 30 of elongate particles have their longitudinal axes extending in a first direction indicated by the arrow 31 at an angle ⁇ to the plane of the security document. In such a configuration, a shift in the absorption spectrum is observed by the viewer between the positions 32 and 33.
- a second or further groups of particles may be aligned so that their longitudinal axes extend in a second direction, which is different from the direction indicated by the arrow 31, at an angle to the plane of the security document.
- various patterns may be observed by a viewer of the authentication device, the various portions of the pattern being formed by the various groups of aligned particles within the authentication device.
- the various parts of the authentication device will exhibit a viewed colour difference depending upon the orientation of the banknote 20 with respect to the viewer.
- nanoparticles used in the authentication device 10 of Figures 1 to 5 are adapted to reflect incident light waves, similar optical effects may be achieved with nanoparticles which act to fluoresce or luminesce light waves therefrom.
- the banknote 40 again includes a subsfrate 41 including a biaxially oriented polymeric film 42 and 2 copolymer outer coatings 43 and 44. Opacifying coatings 45 and 46 are formed on the outer surfaces of the copolymer outer coatings 43 and 44.
- An authentication device 47 is formed at a first location on the banknote 40.
- elongate nanoparticles are positioned within the copolymer outer coating 43 such that their longitudinal axes are substantially parallel with the plane of the banknote 40 and are aligned in a first selected direction.
- a window X is formed through the banknote 40 in the vicinity of the authentication device 47, by leaving that portion of the transparent substrate 41 uncoated by the opacifying coatings 46 and 45.
- the group of aligned nanoparticles located in the copolymer outer layer 43 forming part of the authentication device 47 cover only a portion Y of the width of the window X. Because the absorption spectrum of the nanoparticles is anisotropic, it may act as efficient light polarizers. They do this by selectively absorbing the plane of polarized light at a specific wavelength, as indicated in Figure 4. In this application there is no need to orient the elongate nanoparticles at an angle relative to the viewer and the elongate nanoparticles are simply laid down with their longitudinal axes parallel to the banknote surface.
- Patterns may be formed within the window X by providing a further group or groups of elongate nanoparticles having their longitudinal axes aligned along a different direction to that of the first group of nanoparticles.
- a first group of nanoparticles 48 in the copolymer outer coating 43 may be oriented along a first direction
- other groups 49 and 50 of elongate nanoparticles may be formed in the opposing copolymer outer coating 44 in areas within the boundaries of the window X, but outside the boundaries of the first group of elongate nanoparticles Y.
- the latent image thus formed when the banknote is viewed in transmission is invisible as all the elongate nanoparticles have their longitudinal axis normal to the viewing direction, thus producing a uniform colour.
- the analyzer may be provided at a second location on the banknote 40 so that, as seen in Figure 7, the banknote 40 may be folded so as to superpose the analyzer 51 and the polarizing authentication device 47.
- the analyzer may be provided on a separate document or device. For example, 2 banknotes or other security documents including the authentication device 47 may be used to verify each other.
- the analyzer 51 is formed by locating elongate nanoparticles within a window Z of the banknote 40.
- the elongate nanoparticles in the analyzer 51 have their longitudinal axes aligned along a direction coincident with the direction along which one or more groups of particles forming part of the authentication device are aligned.
- Figure 8 provides an illustration of this.
- the first group of elongate nanoparticles are located in the outer copolymer layer 43 with their longitudinal axes extending in the direction indicated by the arrow 52.
- the groups 49, 50 of elongate nanoparticles in the copolymer outer layer 44 have their longitudinal axes extending in the direction indicated by the arrow 53.
- the window 47 of the banknote is examined by a user, the latent pattern or image formed by the groups 48 to 50 of elongate nanoparticles is not visible to the user.
- the elongate nanoparticles in the groups 48 to 50 are so disposed in the copolymer outer layers 43, 44 so as to polarized incident light waves.
- the group of elongate nanoparticles in the analyzer 51 have their longitudinal axes extending in the direction indicated by the arrow 53.
- extinction of image occurs where the longitudinal axis of the elongate nanoparticles in the analyzer 51 are orthogonal with the longitudinal axes of the elongate nanoparticles in the group 48 of nanoparticles in the polarizer 47.
- the resultant exposed image is referenced 54.
- Figure 9 schematically illustrates the fact that the group 48 of elongate nanoparticles may be applied to one outer layer of the banknote 40, whilst the groups 49, 50 may be applied to the opposing side of the banknote 40.
- the groups 49, 50 may be applied to the opposing side of the banknote 40.
- one or more or all groups of nanoparticles forming such a pattern may be formed in an outer layer.
- the nanoparticles may be located in the central polymeric film 42.
- a ligand with a sulphur atom at one end and a siloxal group at the other can be used to attach itself to the gold surface of the elongate nanoparticle via the sulphur atom.
- the distal end of the ligand is then polymerized via a sol-gel reaction to produce a glassy shell around the gold nanoparticle core.
- the thickness of this shell is easily controlled and so different grating periods are attainable.
- grating structure produced according to this technique are totally shielded from their immediate environment and further more behave in the same manner as silica. This enables the convenient orientation of the elongate nanoparticles via the presence of a static electric field.
- nanoparticles located in the outer layers of the substrate 2 it is of course possible to locate the nanoparticles elsewhere within the substrate.
- an authentication device based upon the optical properties and effects of nanoparticles may be created in which the nanoparticles are centrally located within the substrate 2, providing a window is located in the opacifying layer 45 or 46 for viewing of these optical effects.
- acoustic or audio waves to elucidate nanoparticle size may also be used in the context of the present invention.
- the inclusion of nanoparticles at any convenient location within the substrate 2 results in an authentication device which does not require visual access to the location within the substrate 2 at which the nanoparticles are held.
- the authenticity of the security document can be verified by observation of the response to the acoustic waves and verification that the response corresponds to that of an object containing nanoparticles of the size expected to be within that security document.
- low concenfrations of nanoparticles may be incorporated into banknote film, each denomination having different sized nanoparticles. Authentication and denomination are determined by measuring the different responses to the exciting audio frequency.
- the spectra shown in Figure 4 may be achieved without a specific orientation of the longitudinal axes of the nanoparticles. Accordingly, in authentication devices based upon this optical effect, the nanoparticles may easily be formed in the substrate 2 or subsequently located in an outer layer of the substrate by a variety of techniques.
- the particles may be supported on a fransfer foil or film and a heated die is used to press the transfer film to the outer layer of the substrate and so transfer the nanoparticles into the outer layer of the substrate.
- various alignment techniques may be used.
- the nanoparticles may be formed in one or more layers of the substrate, and heat applied to at least a first portion of the layer so that the nanoparticles are free to orient themselves.
- An external field such as an electric, magnetic, electromagnetic, or mechanically induced stress field, may then be applied so as to orient the mnanoparticles in one or more desired directions.
- the layer may then be allowed to cool so as to fix the orientation of the nanoparticles.
- the nanoparticles may be oriented in a uniform direction on a transfer film or foil. The aligned elongate nanoparticles are then transferred onto the substrate by an embossing technique.
- the films are transferred from the release film, although in other embodiments the film may be perforated by the die and also transferred onto the substrate, thereby forming a protective layer of the nanoparticles.
- the transfer process also embosses the substrate.
- the die has a saw-tooth pattern and again various components of an image have their saw-tooth patterns arranged at different angles relative to each other.
- the profile of the die in this case is much greater than the length of the elongate nanoparticles.
- Techniques for achieving alignment of the elongate nanoparticles include the use of surface tension, static electricity, magnetic fields and entropic forces.
- stretching, the use of static or periodically changing EM fields and self-assembly may be used as ways of orienting the particles.
- the elongate nanoparticles may be deposited into pores formed in the outer layer of the substrate.
- the nanoparticles may be synthesized according to this technique by anodizing the polymer outer layer of the substrate to produce uniform pores in the polymer spaced at regular intervals. The anodizing conditions determine the pore diameter and density.
- the material used to produce the elongate nanoparticles, such as silver or gold, may then be elecfrodeposited into the pores. The elecfrodeposition time period determines the length of the longitudinal axis of the nanoparticle in the pore.
- the substrate 2 may be exposed to an energy source S whilst the security document is oriented at an angle other than perpendicular to the direction of a beam from the energy source.
- the tracks thus left in the substrate are therefore oriented at that angle to the normal.
- the fracks are then able to be used directly as pores for elecfrodeposition or may be etched to increase their dimensions prior to elecfrodeposition.
- At least a first outer surface of the substrate may be coated with a layer containing spherical nanoparticles, and heat then applied to the layer to allow the spherical nanoparticles to self assemble into a concatenated series.
- Heat may be applied to the layer as a whole, or to one or more selected portions of the layers.
- Concatenated series of nanoparticles, or "beads-on-a- string" may thus be created in each of the selected portions.
- the aspect ratio of the nanoparticle structures may be controlled by the temperature and duration of the heating.
- nanoparticles may be used to incorporate covert, machine readable structures into the security document of the present invention.
- Such structures take advantage of the spectroscopic signals that are unique to nanoparticles, and include narrow bandwidth photoluminescence, polarised photoluminescence, surface enhanced Raman effects, acoustic and photoacoustic effects, magnetic effects and the like.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Composite Materials (AREA)
- Business, Economics & Management (AREA)
- Accounting & Taxation (AREA)
- Finance (AREA)
- Credit Cards Or The Like (AREA)
- Laminated Bodies (AREA)
Abstract
Description
Claims
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AUPP6244A AUPP624498A0 (en) | 1998-09-29 | 1998-09-29 | Security document including a nanoparticle-based authentication device |
AUPP624498 | 1998-09-29 | ||
PCT/AU1999/000830 WO2000018591A1 (en) | 1998-09-29 | 1999-09-28 | Security document including a nanoparticle-based authentication device |
Publications (1)
Publication Number | Publication Date |
---|---|
EP1152907A1 true EP1152907A1 (en) | 2001-11-14 |
Family
ID=3810462
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP99950399A Withdrawn EP1152907A1 (en) | 1998-09-29 | 1999-09-28 | Security document including a nanoparticle-based authentication device |
Country Status (7)
Country | Link |
---|---|
EP (1) | EP1152907A1 (en) |
AU (2) | AUPP624498A0 (en) |
BR (1) | BR9914100A (en) |
CA (1) | CA2345344A1 (en) |
ID (1) | ID29627A (en) |
TW (1) | TW442407B (en) |
WO (1) | WO2000018591A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US11945253B2 (en) | 2019-05-20 | 2024-04-02 | Crane & Co., Inc. | Use of nanoparticles to tune index of refraction of layers of a polymeric matrix to optimize microoptic (MO) focus |
Families Citing this family (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE10116315A1 (en) * | 2001-04-02 | 2002-10-10 | Giesecke & Devrient Gmbh | Color coding for marking objects |
US7044376B2 (en) | 2003-07-23 | 2006-05-16 | Eastman Kodak Company | Authentication method and apparatus for use with compressed fluid printed swatches |
JP5158921B2 (en) * | 2005-12-28 | 2013-03-06 | 日本発條株式会社 | Identification medium |
US20070281177A1 (en) * | 2006-05-31 | 2007-12-06 | Cabot Corporation | Colored Reflective Features And Inks And Processes For Making Them |
US8790459B2 (en) | 2006-05-31 | 2014-07-29 | Cabot Corporation | Colored reflective features and inks and processes for making them |
JP5129935B2 (en) * | 2006-06-13 | 2013-01-30 | 日東電工株式会社 | Sheet-like composite material and manufacturing method thereof |
GB0613306D0 (en) * | 2006-07-04 | 2006-08-16 | Rue De Int Ltd | Security device |
DE102006043107A1 (en) | 2006-09-07 | 2008-03-20 | Bundesdruckerei Gmbh | Security and / or value document with SERS-active particles |
EP2042576A1 (en) | 2007-09-20 | 2009-04-01 | Agfa-Gevaert | Security laminates with interlaminated transparent embossed polymer hologram. |
US20090141355A1 (en) * | 2007-09-25 | 2009-06-04 | Opsec Security Group, Inc. | Security device, reflective layer therefor, and associated method |
DE102007061979A1 (en) * | 2007-12-21 | 2009-06-25 | Giesecke & Devrient Gmbh | security element |
EP2286981B1 (en) | 2009-08-22 | 2012-12-12 | EV Group E. Thallner GmbH | Process for heat embossing a polymer layer |
EP2332738B1 (en) | 2009-12-10 | 2012-07-04 | Agfa-Gevaert | Security document with security feature on edge |
EP2335938B1 (en) | 2009-12-18 | 2013-02-20 | Agfa-Gevaert | Laser markable security film |
EP2335937B1 (en) | 2009-12-18 | 2013-02-20 | Agfa-Gevaert | Laser markable security film |
EP2399756B1 (en) | 2010-06-23 | 2017-07-26 | Fábrica Nacional De Moneda Y Timbre | Security element |
JP6009549B2 (en) * | 2011-06-02 | 2016-10-19 | ファブリカ、ナシオナル、デ、モネダ、イ、ティンブレ−レアル、カサ、デ、ラ、モネダFabrica Nacional De Moneda Y Timbre−Real Casa De La Moneda | Using Raman markers to authenticate the authenticity of security documents |
US9387719B2 (en) | 2013-10-28 | 2016-07-12 | Honeywell International Inc. | Cold-worked metal articles including luminescent phosphor particles, methods of forming the same, and methods of authenticating the same |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5145518A (en) * | 1990-06-27 | 1992-09-08 | Xerox Corporation | Inks containing block copolymer micelles |
US5517338A (en) * | 1992-10-20 | 1996-05-14 | Monsanto Company | Composite mirrors |
US5766764A (en) * | 1996-06-04 | 1998-06-16 | The Boeing Company | Nanoscale amorphous magnetic metals |
JPH1069629A (en) * | 1996-08-27 | 1998-03-10 | Dowa Mining Co Ltd | Coating type magnetic recording medium having double layer structure |
US5733480A (en) * | 1996-09-24 | 1998-03-31 | Quantum Chemical Corporation | Semiconductive extrudable polyolefin compositions and articles |
US6045925A (en) * | 1997-08-05 | 2000-04-04 | Kansas State University Research Foundation | Encapsulated nanometer magnetic particles |
-
1998
- 1998-09-29 AU AUPP6244A patent/AUPP624498A0/en not_active Abandoned
-
1999
- 1999-09-28 EP EP99950399A patent/EP1152907A1/en not_active Withdrawn
- 1999-09-28 AU AU63205/99A patent/AU755091B2/en not_active Ceased
- 1999-09-28 BR BR9914100-0A patent/BR9914100A/en not_active Application Discontinuation
- 1999-09-28 CA CA002345344A patent/CA2345344A1/en not_active Abandoned
- 1999-09-28 TW TW088116601A patent/TW442407B/en not_active IP Right Cessation
- 1999-09-28 WO PCT/AU1999/000830 patent/WO2000018591A1/en not_active Application Discontinuation
- 1999-09-28 ID IDW20010729A patent/ID29627A/en unknown
Non-Patent Citations (1)
Title |
---|
See references of WO0018591A1 * |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US11945253B2 (en) | 2019-05-20 | 2024-04-02 | Crane & Co., Inc. | Use of nanoparticles to tune index of refraction of layers of a polymeric matrix to optimize microoptic (MO) focus |
Also Published As
Publication number | Publication date |
---|---|
CA2345344A1 (en) | 2000-04-06 |
AUPP624498A0 (en) | 1998-10-22 |
TW442407B (en) | 2001-06-23 |
BR9914100A (en) | 2001-07-31 |
AU755091B2 (en) | 2002-12-05 |
ID29627A (en) | 2001-09-06 |
AU6320599A (en) | 2000-04-17 |
WO2000018591A1 (en) | 2000-04-06 |
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