CN114633574A - Safety line or strip with dynamic visual three-dimensional effect - Google Patents

Abstract

The present invention relates to the field of protecting value documents and value goods against counterfeiting and illegal copying. The invention relates in particular to a method for producing a security thread or stripe and an optical security element, comprising a substrate and a coating comprising pigment flakes and a transparent radiation-curable linking resin, said coating being supported by said substrate, wherein said pigment flakes comprise a magnetic or magnetizable material for magnetically aligning said pigment flakes; the coating passes through a magnetic field with a specific structure so that the pigment flakes are arranged according to a corresponding rule to form patterns and form a highly dynamic visual motion effect and stereoscopic impression.

Description

Safety line or strip with dynamic visual three-dimensional effect

Technical Field

The present invention relates to security threads or stripes to be incorporated into security documents or onto security film materials or as characteristic security elements, which exhibit a highly dynamic visual motion effect and a three-dimensional impression when tilted.

Background

Security threads having a pronounced characteristic effect are known to the person skilled in the art as effective means of protecting security documents or goods against forgery, in particular banknotes. Security threads are metal-or plastic-filaments that are incorporated into substrates for printing security documents or for banknotes during the manufacturing process. The security thread or strip carries specific security elements for the public and/or machine authentication of security documents, in particular banknotes. Security elements suitable for this purpose include, but are not limited to, metallizations, optically variable compounds, luminescent compounds, microtext and magnetic components.

WO 2011/107527 a1 discloses wires or strips comprising a plastic foil with a hardened coating comprising oriented magnetic or magnetizable pigment particles, in particular optically variable magnetic or magnetizable pigment particles, the orientation of which represents graphical information.

US 7, 047, 883 discloses the generation of a dynamic light-variable effect called "rolling bar" member. The "scroll bar" members provide the optical illusion of motion to the image of oriented magnetic or magnetizable pigments. US 7, 517, 578 and WO 2012/104098 a1 disclose "double scroll bar" and "triple scroll bar" members, respectively, which appear to move relative to each other when tilted. The printed "rolling bar" type image shows a band or contrasting band that appears to move ("roll") as the image is tilted relative to the viewing angle. Such images are known to be easily recognized by ordinary people and the illusion appearance cannot be reproduced by common office equipment for color scanning, printing and copying. The "scroll bar" members are based on a particular orientation of magnetic or magnetizable pigments. In particular, the magnetic or magnetizable pigments are arranged in a curved manner, following either a convex curvature (also referred to in the art as a negative-curved orientation) or a concave curvature (also referred to in the art as a positive-curved orientation).

WO 2012/104098 a2 discloses a method of manufacturing a "triple spool" member, the method comprising the steps of: a) applying a coating composition comprising magnetic or magnetizable pigment particles to a substrate; b) orienting the magnetic or magnetizable pigment particles according to a first curved surface by applying a first magnetic field; c) selectively hardening the applied coating composition in a first region, thereby fixing the magnetic pigment particles in their position and orientation; d) orienting said magnetic or magnetizable pigment particles in the unhardened portion of the coating composition according to a second curved surface by applying a second magnetic field; e) hardening the applied coating composition in the second region, thereby fixing the magnetic pigment particles in their position and orientation. In order to achieve a region containing pigment particles that follow a negative curvature orientation and a region containing pigment particles that follow a positive curvature orientation, the disclosed method requires that the pigment particles be oriented by applying a magnetic field generating means from the bottom of the substrate on the one hand, and a magnet from the top of the substrate on the other hand. At the same time, the hardened region is segmented, and the continuity of the arrangement is lost, thereby losing the possibility of designing new optical characteristics for the joint region.

WO2015/121028 discloses a method for producing a one-sided viewing element with a continuous concave-convex curve, which method forms an orientation hardening of magnetic or magnetizable pigment particles following a convex curvature, respectively in transparent areas on both sides of a substrate, by means of a joint complementation, so as to have a continuous wavy line structure orientation when viewed on one side. The step of applying a magnet from the top of the substrate is reduced, resulting in an increase in printing speed. However, the magnetic or magnetizable pigments of the concave curve and the convex curve are distributed on two sides, so that the visual difference of the far and near view scroll bars is reduced, the far and near view structure is not easy to see, and the continuity of arrangement is lost, so that the possibility of designing new optical characteristics for the connection area is lost.

There is still a need to provide complex security threads or stripes that combine high visual appeal with highly complex designs to further improve the counterfeit or illegal copying resistance of security documents containing the same. There is also a need for more efficient methods for manufacturing such complex security threads or stripes.

Disclosure of Invention

Security threads or stripes and methods of making such security threads or stripes are disclosed and claimed herein, the security threads or stripes comprising a substrate and a coating comprising pigment flakes, the coating being supported by the substrate; wherein each of the pigment flakes comprises a magnetic or magnetizable material for magnetically aligning the pigment flakes, and the pigment flakes are aligned to follow a convex-concave-convex-concave periodic curvature (or "continuous wavy line curvature") to form an aligned pattern and are hardened; the magnetic field of its wave line camber characteristic is through two sets of same two liang of adjacent homopolar magnetic poles arrange equidistant or the magnet composite module of equidistant range in opposite directions, and the front and back order is placed and there is the displacement that has half interval in the magnetic pole opposite direction to the centre in upper and lower position forms the passageway, the coating passes through the magnet composite module back through the radiation hardening coating around in proper order through the intermediate channel, thereby obtains the pattern of following continuous wave line camber in order to form the range.

The cured coating of pigment flakes formed according to the above method, which is aligned along the curvature of the continuous wavy line, is simple and easy to understand in a one-step forming method. Under normal vertical observation, the top part (namely the peak part) of the convex curvature forms a light band strip, and the light band strip gives a long-shot feeling to people according to the imaging principle of the convex Fresnel reflector; the concave Fresnel reflector imaging principle shows that the light band strips give close-range perception to people, the light band strips of the wave crests and the wave troughs form close-range contrast, bright light and dark light reflecting structures can be formed due to the fact that pigment sheets on two sides of the wave crests or the wave troughs are arranged approximately in a symmetrical angle mode, hollow characters or patterns can be made on the corresponding portions of the coatings in the middle between the wave crests and the wave troughs of the wave line curvature, and the flashing and hiding effects of light and dark changes can be seen through the characters or the patterns of the hollow coating portions along with the change of the observation angle.

According to the above, the difference between the front distance and the rear distance of the optical band imaging at the wave crest and the wave trough of the near-far view structure formed by the pigment flake arrangement structure of the coating is small, so that the near-far view structure observed by naked eyes is not obvious, the coating is easy to observe to obtain stereoscopic impression, the stereoscopic vision feeling is not obvious when the coating is extremely thin, and some people may not perceive the stereoscopic vision feeling. In order to enable a noticeable three-dimensional impression to be observed even when the coating is extremely thin, the invention also provides a method for producing a security thread or stripe having a three-dimensional dynamic visual effect under an extremely thin ink layer.

A security thread or stripe comprising a substrate and a coating comprising pigment flakes and a transparent radiation curable linking resin, the coating being supported by the substrate, wherein the pigment flakes comprise a magnetic or magnetizable material for magnetically aligning the pigment flakes; the pigment flakes are mainly distributed on both the top and bottom sides of the transparent radiation-curable bonding resin, and are formed on both sides in an arrangement following a plurality of convex or concave curvatures, and the upper and lower surfaces have opposite curvature arrangements; and from left to right a top view forming a convex-concave-convex periodic curvature arrangement; the high-strength and high-permeability metal sheet with low coercive force and high permeability is placed at the same height position of the upper side of each convex curvature magnetic field line of a plurality of adjacent convex curvature magnetic field lines formed by the magnetic field, so that the pigment sheets form convex-concave-convex periodic curvature arrangement and distribution of the top and the bottom of the transparent radiation-curable connecting resin along the extending plane of the upper surface of the metal sheet, and remarkable three-dimensional visual dynamic rolling characteristics are generated on an extremely thin coating.

The security thread or strip with the three-dimensional visual dynamic characteristics decomposes the periodic structure characteristic part of the security thread or strip to obtain the optical anti-counterfeiting element with the three-dimensional layered structure. An optical security element of a three-dimensional layered structure comprising a substrate and a coating comprising pigment flakes and a transparent radiation-curable linking resin, the coating being supported by the substrate, wherein the pigment flakes comprise a magnetic or magnetizable material for magnetically aligning the pigment flakes; the pigment flakes are formed by a fixed magnetic field and are mainly distributed on the top and the bottom of the transparent radiation-curable resin, the upper side and the lower side of the pigment flakes form an arrangement which follows a plurality of convex curvatures or concave curvatures, the upper side and the lower side of the pigment flakes have opposite curvature arrangements, and a convex-concave-convex curvature arrangement is formed in a left-to-right top view; the magnetic field is formed by placing metal sheets with low playing force and high magnetic conductivity smaller than the curvature diameter on the upper side of a convex curvature magnetic field line in a single direction, and the edges of two sides of a self-induced magnetic field with concave curvature formed in the middle of the upper surface of the metal sheet can form a convex curvature magnetic field in a 1-2MM space on the upper side of the metal sheet under the influence of the magnetic self-induction of the metal sheet on the convex curvature magnetic field in the single direction, so that pigment sheets form the distribution and the arrangement of the characteristics in the diameter range of the convex curvature magnetic field in the single direction in an extension plane of the upper surface of the metal sheet.

The principle of forming the characteristic of the obvious layered rolling strip is that besides the magnetic self-induction of the metal sheet with low coercive force and high permeability under the influence of the convex curvature magnetic field in the single direction on the single side forms the self-induction magnetic field with concave curvature in the middle of the upper surface of the metal sheet, and simultaneously the two side edges of the metal sheet absorb the magnetic field lines of the convex curvature magnetic field in the single direction on the single side, so that the magnetic field with small diameter and convex curvature is locally formed at the edge, the magnetic field energy level difference distribution is formed on the upper surface of the metal sheet by the magnetic field lines of the magnet at the bottom of the metal sheet penetrating through the metal sheet by the metal sheet with low coercive force and high permeability, the magnetic field is expressed that a magnetically neutral channel exists in the local area around the metal sheet, magnetic fields with opposite directions exist on the two sides of the magnetically neutral channel, and the middle local space of the coating is magnetically neutral, so that the pigment sheets are distributed on the upper side and the lower side of the coating under the action of the magnetic field. The explanation of atomic physics is that the part of the metal sheet with low playing power and high magnetic conductivity, which penetrates through the metal sheet to the original magnetic field line, participates in retarding to change the number of the spinning electrons of the atomic outer layer of the original magnetic field to exponentially increase with the increase of the thickness to form obvious energy level difference, so that the pigment sheet arrangement in the coating can show the three-dimensional characteristic formed by the energy level difference of the magnetic field line, and the explanation of the existing magnetic resistance retardation phenomenon is also met; another explanation for magnetization induction is that during the magnetization process of the metal sheet, magnetic domain transfer in different areas of the upper surface generates corresponding induction magnetic fields to prevent the metal sheet from being magnetized by external magnetic fields, and the principle of the induction magnetic fields can better explain the concave curve part at the top. More experimental results show that the main reason for enabling naked eyes to see the obvious near-far view structure is that magnetic pigment flakes are mainly arranged on the upper surface and the lower surface along concave-convex curves respectively due to the factors of magnetic field energy level difference and induction magnetic field, and in addition, the connecting material is a substance with high light transmittance and high refractive index, so that the imaging has staggered layer displacement (namely horizontal displacement difference of refraction imaging), and meanwhile, the light bands on the two surfaces have opposite moving directions, and the stereo contrast effect is intensified.

Conventionally, the substrate is a plastic film with one or more characteristics of a transparent structure, a holographic structure, an interference type multi-coating optical variable structure, a local reflective layer structure, or a paper substrate.

Conventionally, the pigment flakes are a mixture of one or more of magnetic pigment flakes, magnetic lamellar optically variable pigments and magnetic liquid crystal pigments. The magnetic laminar optically variable pigment is an optically variable pigment with a five-layer or seven-layer structure prepared by vacuum evaporation or sputtering, the middle layer is a magnetic layer, and the material of the magnetic laminar optically variable pigment is iron, cobalt and nickel or oxides thereof, barium ferrite, nickel-chromium alloy or titanium-cobalt alloy; the magnetic liquid crystal pigment is a blend of cholesteric liquid crystal pigment and magnetic powder, or is a three-layer structure magnetic liquid crystal pigment with a magnetic layer in the middle and liquid crystal layers on two sides, and the magnetic powder is made of iron, cobalt and nickel or oxides thereof, barium ferrite, nickel-chromium alloy and titanium-cobalt alloy.

Typically, the metal sheet having low coercive force and high permeability is permalloy, silicon steel, electric steel, or the like, or may be other high permeability soft magnetic metals, alloys, or compounds having one or more of low coercive force and high permeability, or a composite comprising about 25 wt% to about 95 wt% soft magnetic particles dispersed in a non-magnetic material such as natural rubber, synthetic rubber, or plastic polyester resin.

The use of the security thread or stripe described herein for protecting a security document against counterfeiting, imitation or illegal reproduction is described and claimed herein as well as security documents comprising said security thread or stripe, or security threads or stripes as characteristic security elements, printed directly on the surface of an article of value.

Also described and claimed herein are methods of manufacturing a security document comprising a security thread or stripe as described herein and security documents obtained therefrom, said method comprising the steps of: a) manufacturing the security thread or stripe described herein, and b) at least partially embedding in said security document the security thread or stripe obtained under step a), or mounting on the surface of said security document the security thread or stripe obtained under step a).

The method of making the security thread described herein provides more varied stereoscopic visual effects and one-shot printing, lower cost, higher efficiency, and better integrity than prior art security threads or stripes.

Drawings

FIG. 1 is a process set-up for fixing magnetic flux following the curvature of a continuous wavy line to form an aligned pattern of security threads or stripes.

Fig. 2 is a schematic view of the formation of the curvature of a continuous wavy line.

Fig. 3 is a schematic view showing the visual change of curvature of each part of the continuous wavy line.

Fig. 4a is a schematic diagram of the formation of a convex curvature magnetic field, and fig. 4b is a schematic diagram of a magnetic field formed by changing a small metal sheet under the convex curvature magnetic field.

Fig. 5 is a magnetic anchoring device following a convex-concave-convex periodic curvature feature to form an aligned pattern of security threads or stripes.

FIG. 6a is a schematic diagram of the transverse cross-sectional magnetic field of the magnetism fixing device in FIG. 5; fig. 6b is a schematic illustration of the position distribution of pigment flakes in the coating under the fixed magnetic device of fig. 5.

FIG. 7a is a full shot of various views of security threads or stripes following the curvature of successive wavy lines to form an arranged pattern; fig. 7b is a full shot view of various angles of view of security threads or stripes following a convex-concave-convex periodic curvature characteristic to form an arranged pattern.

Detailed Description

Embodiments of the invention will be further described with reference to the accompanying drawings, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below are exemplary embodiments with reference to the drawings, are intended to explain the present invention and should not be construed as limiting the present invention, and any modification, equivalent replacement or improvement made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.

Example one

This example is to produce a security thread or stripe in which the flakes in the coating follow the curvature of a continuous wavy line to form an aligned pattern. As shown in fig. 1, the substrate and the coating are sequentially placed from front to back through two groups of same adjacent magnet combined modules with same-polarity magnetic poles arranged oppositely at equal intervals or arranged at unequal intervals, and have displacement with half interval in the opposite direction of the magnetic poles, and a channel is formed in the middle of the upper position and the lower position, and the coating passes through the magnet combined modules at the front and the rear in sequence through the middle channel and then is subjected to radiation hardening coating, so that a pattern which follows the curvature of a continuous wavy line to form the arrangement is obtained. The coating is generally applied to the substrate by printing (including relief printing, gravure printing, and screen printing), and when the coating passes through the first magnetic assembly module, a periodic discontinuous convex curvature arrangement (as shown in fig. 2) can be formed, and then passes through the second magnetic assembly module, and a desired arrangement of continuous wavy line characteristic curves (the middle wavy line characteristic curve shown in fig. 2) can be obtained by locally correcting the displacement difference. It should be noted that in order to better obtain the arrangement pattern of the wave-line curvature features, the passing speed (i.e. the correction action time) of the second magnetic group module needs to be repeatedly tested to achieve the best effect, and the passing speed is related to the strength of the magnets of the magnetic group, and the action time is shorter as the magnetic field strength is higher. Fig. 7a is an actual pattern of the present embodiment. A plurality of wave crest and wave trough rolling strips can be seen through the vertical observation in the front, certain far and near level stereoscopic impression can be sensed at the wave crest and wave trough positions due to the visual difference of imaging, when the inclined observation is carried out, as the refractive index of most of connecting material resin after curing is 1.47-1.5, when the transparent connecting material in the coating is thick, partial scattered light is filtered out due to the refraction displacement of the light, so that people can easily observe the inclined stereoscopic impression of the arrangement of the pigment sheets of the symmetrical light and shade change part, and meanwhile, the symmetrical light and shade change surface is changed along with the change of the inclined observation angle. As shown in fig. 3, the curvature characteristics of the continuous wavy lines vary from portion to portion. Particularly, hollow characters or patterns can be made at the corresponding part of the coating (namely the symmetrical light and shade change part) in the middle between the wave crest and the wave trough of the wave line curvature, and the light and shade change flashing and hiding effect can be seen by the change of the characters or patterns of the hollow coating along with the change of the observation angle.

In particular, when the substrate material is a thin film having diffractive optical features, multi-layer interference structured optical features, or reflective optical features, more complex optical effects can be imparted by the inventive security thread or stripe.

Example two

This example is to produce a security thread or stripe in which the flakes in the coating follow a convex-concave-convex periodic curvature characteristic to form an aligned pattern. Fig. 5 shows that the device of the safety line or strip of the invention is a device for forming a characteristic magnetic field, a metal sheet with low playing power and high magnetic permeability is provided with magnets which are magnetized in the width direction at the bottom of a metal strip with hollowed-out sides according to the drawing rules, the magnetic poles and the position intervals are shown in the drawing, the shape of the electric furnace steel with the thickness of 1MM which is processed by laser hollowed-out processing is used in the embodiment, the magnets are neodymium iron boron magnets which are magnetized in the width direction, the specification is 5 x 2 x 20MM, the hollowed-out width of the hollowed-out plate is 3 MM, the width of a single metal strip in the middle is 3 MM, and the actual effect of the formed coating is shown in fig. 7 b.

Now briefly analyze the magnetic force line condition of the single-period convex-concave-convex curvature characteristic. Fig. 4a is a diagram showing a conventional convex curvature magnetic field forming diagram, as shown in fig. 4, in which the convex curvature magnetic field lines are relatively simple, and the situation becomes complicated when there is a metal sheet with low coercive force and high magnetic permeability smaller than the curvature diameter (in this example, the diameter size can be simply equivalent to the distance between two magnets), and fig. 4b is a diagram showing a magnetic field formed by a small metal sheet with low coercive force and high magnetic permeability under the convex curvature magnetic field. An opposite induction magnetic field is formed in the space of 1-2MM on the upper surface of the metal sheet, namely the side far away from the magnet, and a magnetic neutral channel space is formed in a partial area near the metal sheet, so that the magnetic pigment sheets in the coating can be distributed on two sides of the magnetic neutral channel space, and a stereoscopic photosensitive belt which can be distinguished by naked eyes can still be generated under the condition of extremely thin coating thickness. We know that the magnetization process of a metal sheet with low playing force and high magnetic permeability under a magnetic field is very complex, because the shape, size and thickness of the metal sheet are greatly different from the change of the original magnetic field, it is risky to change the position of the metal sheet randomly, and we only need to form the periodic structure shown in fig. 4b according to the above description, but the inventor does not strictly follow the design of the metal sheet shown in fig. 4b in the metal sheet shown in fig. 5, the top of a magnet in the metal sheet shown in fig. 5 is also provided with a metal strip with a width larger than that of the magnet to guide the magnetic force line, a single convex curvature magnetic field is formed in the middle of a hollow strip, and experiments prove that the width of the hollow strip is less than 5MM to enable the magnetic force line emitted by the magnet on one side to cross the hollow strip to reach the magnet on the other side to form a closed loop so as to form the single convex curvature magnetic field in the middle empty area, and if the hollow width is too large, a fault is formed, and dense magnetic lines of force can be formed only on two sides of the metal strip above the magnet. In addition, the fixed magnetic device shown in fig. 5 can be applied to ink coatings with the pigment flake content of 10-50%, and highly dynamic visual motion effect and stereoscopic impression can be obviously observed. Fig. 6a is a cross-sectional view of the device of fig. 5, showing more visually the approximate distribution of magnetic field lines, and fig. 6b is a schematic view showing the position distribution of pigment flakes in the coating under the magnetizing device of fig. 5.

The security thread or stripe described herein is particularly useful for protecting security documents against counterfeiting, imitation or illegal reproduction. Also described herein are security documents comprising said security threads or stripes. Examples of security documents include, but are not limited to, value documents and value goods. Typical examples of value documents include, but are not limited to, banknotes, dees, tickets, cheques, receipts, tax stamps and stamps, contract parties, identity documents such as passports, identity cards, visas, bank cards, credit cards, transaction cards, access documents, entrance tickets and the like. By a commodity of value is meant a packaging material, in particular for the pharmaceutical, cosmetic, electronics or food industry, which may comprise one or more security features to secure the contents of the package, e.g. a genuine drug. Examples of such packaging materials include, but are not limited to, labels, such as authenticating brand labels, tamper evident labels, and seals. The security document described herein is preferably selected from banknotes, identity documents such as passports, identity cards, driver's licenses and the like, more preferably banknotes. The security threads or stripes described herein may also be printed directly onto the surface of an article of value as the security threads or stripes of a characteristic security element.

Claims (6)

1. A security thread or stripe comprising a substrate and a coating comprising pigment flakes and a transparent radiation curable linking resin, the coating being supported by the substrate, wherein the pigment flakes comprise a magnetic or magnetizable material for magnetically aligning the pigment flakes; wherein the pigment flakes are aligned to follow the curvature of the continuous wavy line to form an aligned pattern and radiation cured; the magnetic field of its wave line camber characteristic is through two sets of same two liang of adjacent homopolar magnetic poles arrange equidistant or the magnet composite module of equidistant range in opposite directions, and the front and back order is placed and is had the displacement of half interval in the magnetic pole opposite direction to the centre in upper and lower position forms the passageway, the coating passes through the middle passageway in proper order behind the magnet composite module of front and back through the radiation hardening coating, thereby obtains the pigment piece and follows the pattern of continuous wave line camber in order to form the range.

2. An optical security element of a three-dimensional layered structure comprising a substrate and a coating comprising pigment flakes and a transparent radiation-curable linking resin, the coating being supported by the substrate, wherein the pigment flakes comprise a magnetic or magnetizable material for magnetically aligning the pigment flakes; the pigment flakes are formed by a fixed magnetic field and are mainly distributed on the top and the bottom of the transparent radiation-curable resin, the upper side and the lower side of the pigment flakes form an arrangement which follows a plurality of convex curvatures or concave curvatures, the upper side and the lower side of the pigment flakes have opposite curvature arrangements, and a convex-concave-convex curvature arrangement is formed in a left-to-right top view; the magnetic field is formed by placing metal sheets with low playing force and high magnetic conductivity smaller than the curvature diameter on the upper side of a convex curvature magnetic field line in a single direction, and the edges of two sides of a self-induced magnetic field with concave curvature formed in the middle of the upper surface of the metal sheet can form a convex curvature magnetic field in a 1-2MM space on the upper side of the metal sheet under the influence of the magnetic self-induction of the metal sheet on the convex curvature magnetic field in the single direction, so that pigment sheets form the distribution and the arrangement of the characteristics in the diameter range of the convex curvature magnetic field in the single direction in an extension plane of the upper surface of the metal sheet.

3. A security thread or stripe comprising a substrate and a coating comprising pigment flakes and a transparent radiation curable linking resin, the coating being supported by the substrate, wherein the pigment flakes comprise a magnetic or magnetizable material for magnetically aligning the pigment flakes; the pigment flakes are mainly distributed on both the top and bottom sides of the transparent radiation-curable bonding resin, and are formed on both sides in an arrangement following a plurality of convex or concave curvatures, and the upper and lower surfaces have opposite curvature arrangements; and from left to right a top view forming a convex-concave-convex periodic curvature arrangement; the high-altitude position of the upper side of each convex curvature magnetic field line of a plurality of adjacent convex curvature magnetic field lines formed as a magnetic field is provided with a metal sheet with low playing force and high magnetic conductivity, the metal sheet is smaller than the curvature diameter, so that the pigment sheets form convex-concave-convex periodic curvature arrangement and distribution of the top and the bottom of the transparent radiation-curable connecting resin along the extending plane of the upper surface of the metal sheet, and remarkable three-dimensional visual dynamic rolling characteristics are generated on an extremely thin coating.

4. The security thread or stripe according to claim 1, wherein hollowed-out text or pattern is formed on the corresponding portion of the coating at the middle portion between the peaks and the valleys of the curvature of the wavy line, and bright light and dark light reflecting structures are formed due to the approximately symmetrical arrangement of the pigment flakes on the two sides of the peaks or the valleys, and the text or pattern on the hollowed-out portion of the coating can be seen to have a flashing and hiding effect with the change of the observation angle.

5. The security thread or stripe according to claim 3, wherein the substrate is a plastic film or paper substrate having one or more features selected from the group consisting of a plastic film having a partially or wholly transparent structure, a resin film having a holographic structure, a polymer film having an interference type multi-coated optically variable structure, a polymer film having a partially reflective layer structure.

6. The security thread or stripe according to claim 3, wherein the metal flakes having low coercive force and high permeability may also be other high permeability soft magnetic metals, alloys or compounds having one or more of low coercive force and high permeability, or composites comprising from about 25% to about 95% by weight soft magnetic particles dispersed in a non-magnetic material, such as natural rubber, synthetic rubber or plastic polyester resin.

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