MXPA06006860A - Security article with multicoloured image - Google Patents

Abstract

A security article (10) is provided having a multicoloured image (14) and which comprises a first layer of transparent polymeric material (11) carrying parts of an image (14) formed in a first colour (21);and at least one other layer of transparent polymeric material (12) carrying parts of the image (14) formed in a different colour (22). The layers are laminated together with the parts of the image (14) formed in the first (21) and different colours (22) superposed over one another, whereby the colours (21, 22) combine to form a multicoloured image (14) in the laminated security article (10). In one embodiment, the multi coloured image is viewable from both sides of the security article, and in another form an opaque layer may be provided on one side of the transparent layers to provide a background for viewing the image in reflection from one side of the article. The parts of the image formed by different colours in the respective layers are preferably embedded in the layers, eg by a laser marking process, to form a tamper evident security article.

Description

SECURITY ARTICLE WITH MULTICOLOR IMAGE FIELD OF THE INVENTION This invention relates to security articles that have multi-colored or multi-color images, and in particular, but not exclusively has to do with security items such as passports, driver's licenses, cards of identification and other security documents. This also refers to the methods for manufacturing security items with images of various colors. BACKGROUND AND BRIEF DESCRIPTION OF THE INVENTION It is known to provide security documents, such as bank notes, checks and certificates or the like, with a wide variety of security devices, which provide verification or authenticity and protection against copying or forgery. . In the case of passports, identification cards and the like, in particular in view of the requirements in terms of increasing security levels, it is important to provide a security article that includes personalized information, such as a photograph of various colors of the carrier, which protects it from fraudulent alterations, for example, by removing the photograph and inserting a replacement photo.

It is therefore desirable to provide an tamper-proof or counterfeit security article which has a multi-color image. It is also desirable to provide effective methods for manufacturing such security articles with multi-color images. According to a first aspect of the invention there is provided here a security article having a multi-color image and comprising: a first layer of transparent polymeric material bearing portions of an image formed in a first color; at least one other layer of transparent polymer material carrying portions of said image formed in at least one different color; where the layers are laminated together with the parts of the image formed in the first and the different colors superposed one on top of the other, whereby the colors are combined to form a multi-colored image in the laminated security article, the image of Several colors that can be observed on both sides of the security article. According to a second aspect of the invention there is provided here a method for manufacturing a security article having a multi-color image, wherein the method comprises: providing a first layer of transparent polymeric material; providing at least one other layer of transparent polymer material; forming the parts of an image in a first color in or on the first layer; forming the parts of said image in at least one different color in or on said at least the other layer; and laminating the layers together to form a laminated safety article, wherein, in the laminated safety article, the parts of the image formed in the first and the different colors overlap one another, thereby combining the colors to form a multi-colored image which can be seen on both sides of the laminated safety article. It is possible to form a multi-color image from two superimposed colors, and in this case the step of laminating together the layers of transparent polymeric material can be carried out either before or after the parts of the image are formed in the different colors in the respective layers. Preferably, however, the laminated security article has a third layer of transparent polymeric material carrying portions of said image in a different third color. For example, the first layer may carry said image formed in a magenta red, the second layer may carry said image formed in a green or yellow and the third layer may carry said image formed in blue or cyan. Preferably, the colors of the image formed in the different layers are primary or complementary colors. The laminated security article may include an additional layer of transparent polymer material carrying portions of said image formed in a dark color, for example, black. The dark parts of the image provide more depth and definition to the image of various colors. Preferably, a laser marking process is used to apply the image formed in the different colors to the different layers. In the laser marking process, a multi-color image which is required to be formed in the laminated security article can be scanned by an appropriate program in a digital image and separated into individual primary or complementary colors. The laser marking process is used to apply the parts of the image formed in the first color to the first transparent layer, then the laser marking process is used to apply the parts of the image formed in the second color to the second transparent layer. The laser marking process can also be used to apply the parts of the image formed in different colors to the third and subsequent layers. There are several laser marking processes which could be used in the present invention. For example, a laser printing process could be used to print the parts of the image in their respective colors on each layer of transparent polymeric material. In another form of the laser marking process, patches of pigments of different colors can be printed on the layers of transparent polymeric material and the negative parts of the image are vaporized using laser radiation in such a way that the positive parts of the image in the different colors remain on the different layers to form the image of several colors when the layers are overlapped and laminated together. Such a laminated security article could contain security dyes or destructive layers to indicate alterations with heat or chemicals or other attempts to delaminate the security article. However, a laser marking process is preferred which forms the parts of the image in the different colors indelibly in the different layers. Thus, any alteration of the security article by delamination and an attempted alteration of the parts of the image formed in the different colors will be evident. Preferably, a process is used which forms the different parts of the image in the different colors embedded within the respective layers of transparent polymeric material. According to a third aspect of the invention there is provided here an evident tampering or tamper security article, which has a multi-color image and which comprises: a first layer of transparent polymeric material containing portions of an image formed in a first color embedded within said first layer; at least one other layer of transparent polymeric material containing portions of said image formed in at least one different color embedded within said at least one other layer; wherein the layers are laminated together with the parts of the image formed in the first and the different colors superposed one on top of the other, whereby the colors are combined to form a multi-colored image in the laminated security article.

One or more of the layers may comprise a single transparent polymeric film or substrate into which the respective parts of the image are embedded. Alternatively, one or more of the layers may comprise a transparent polymeric substrate having a transparent polymeric film on at least one surface into which the respective parts of the color image are embedded. The parts of the image formed in different colors in the respective layers can be impregnated into the layers using layers of transparent polymer material, each containing a respective latent color-forming pigment. When such a polymeric material is exposed to laser radiation of a wavelength particles, a color marking is formed within the polymeric material by a photochemical reaction between the latent pigment, the polymer and the laser energy. According to a fourth aspect of the invention, there is provided here a method for manufacturing a tamper evident or tamper security article, which has a multi-color image, wherein the method comprises: providing a first layer of transparent polymeric material which contains a first latent color forming material; providing at least one other layer of transparent polymeric material containing a different color-forming material; forming the parts of an image in a first color by exposing the at least one other layer to the laser radiation to reveal the latent color forming material in the first layer; forms the parts of the image in a different color exposing said at least one other layer to the laser radiation to reveal the different latent color forming material in said at least one other layer; and laminating the layers together with the parts of the image formed in the first and the different colors superposed one on top of the other, whereby the colors are combined to form the multi-colored image in the laminated security document. The polymeric material or the materials for the layers containing the latent color-forming materials are conveniently chosen in such a way that the laser only causes the color marking by developing the latent color marking materials without causing the melting or melting or the abrasion of the material or polymeric materials. Typical polymers that are not sensitive to laser radiation in the infrared (IR) and ultraviolet (UV) regions include polypropylene, polyethylene (low density, high density or linear low density), and mixtures of these polymers . The typical thicknesses of such polymers, suitable for the present invention, fall substantially within the range of about 20 microns to about 200 microns. A thin layer of a low melting point polymer can be co-extruded on one or both sides of a polymeric base film to form at least one of the layers in which a color forming material is provided. The color-forming material can be provided in either the polymer-based film or in the co-extruded layers. The co-extruded thin layers would have a thickness that falls substantially within the range of about 2 microns to about 50 microns. Suitable materials for the co-extruded layers include: metallocene polyethylene, and random copolymers or terpolymer of ethylene, butylene or propylene. The latent color-forming pigments are preferably present in the layers of transparent polymer material at a concentration which is sufficiently low so as not to affect the clarity of the transparent polymeric material. Preferably, the concentration of the color-forming pigment in the transparent polymeric material falls substantially within the range of from about 2.0 to about 0.5% by weight of the polymeric material. The layers of polymeric material containing the latent color-forming pigments can be produced by premixing a batch of polymer which is mixed with the appropriate latent color-forming pigment. An example of a color pigment suitable for use in the present invention is a pigment manufactured by CIBA SC Holding A G which can develop a color when irradiated with a laser emitting UV light. Such color-forming pigments may include a latent acid, a color former and optionally other ingredients as described in WO 02/101462. Other examples of suitable color-forming pigments include the range of IRIODIN LS pigments (laser-sensitive) (IRIODIN is a Trade Mark of Merck KGaA). The principle of color formation with IRIODIN LS pigments from Merck is based on a carbonization and surface formation between mica pigments coated with Ti02, the polymer and the laser energy. Typically such pigments develop color when irradiated with a laser that emits IR radiation. There are a number of laser marking processes which can be used in the present invention, including, a beam deflection technique (a vector process); masking techniques; and dot matrix techniques. For variable data, required for personalization, beam deflection and dot matrix techniques are more appropriate. A tamper evident security article having a multi-color image according to the invention is particularly suitable for use in security documents which contain personal information, such as a passport, driver's licenses, credit cards that contain a photograph of the carrier. However, it will be appreciated that a security article according to the invention can be applied, pasted or attached to, contained or incorporated into other types of documents and articles, such as bank notes, checks, certificates, admission tickets and other credentials and items that require a multi-colored image of tampering or obvious forgery for authentication and / or protection against copying or theft. In the case of a passport, a security article according to the first or third aspect of the invention could be secured to, or be part of, a page of the passport after lamination with the multi-color image comprising a photograph of the passport holder.

Alternatively, two or more of the layers of transparent polymeric material could be sewn or otherwise incorporated into a passport booklet prior to customization by forming the image parts in different colors in or on the transparent layers, with the transparent layers that are laminated together subsequently.

In a particularly preferred embodiment, the layers of transparent polymer material carrying the parts of the image in different colors are laminated together providing a lamination coating between at least two adjacent layers of transparent polymeric material. Alternatively, and / or additionally, heat and / or pressure is used to laminate together the layers of transparent polymeric material. In a booklet such as a passport, at least one opaque (for example, white) page adjacent to a page formed by the laminated security article can help improve the appearance of the multi-color image. As the multi-colored image of a security article according to the first aspect of the invention is visible from both sides, opaque pages are preferably provided on both sides of the security article when it forms a page of a booklet, such as a passport.

A tamper evident tampering security article, according to the third aspect of the invention, is not necessarily visible from both sides and may include an opaque layer on one side of the transparent layers containing parts of the image in different colors , such that the multi-colored image in the laminated security article is only visible in reflection from one side of the article. A laminated security article according to the invention may include additional security features to improve its security against alteration, forgery and / or copying. For example, layers containing layers of the image formed in different colors may include printed information and / or other security features, printed or otherwise. Printed information or other security features could be added to one or more of the clear polymeric layers prior to lamination. The laminate article can be arranged in such a way that a layer provided with the printed information or other security features breaks or cohesively fractures, but with the parts of the image formed in different colors that remain intact. Additional printed security features may include one or more of the following: printed shadow images; images printed with optically variable inks; and / or images recorded from front to back. BRIEF DESCRIPTION OF THE DRAWINGS Some preferred embodiments of the present invention will now be described by way of example only, with reference to the accompanying drawings in which: Figure 1 is a perspective view of a laminated safety article according to the invention; Figure 2 is a plan view showing the individual layers of the security article of Figure 1; Figure 3 is a sectional view through the layers forming the laminated security article of the invention; Figure 4 is a sectional view similar to Figure 3 of a modified laminated safety article; Figure 5 is a sectional view similar to Figure 3 of another modified security article; Figure 6 is a sectional view similar to Figure 5 of a modified additional embodiment; Figure 7 is a view similar to Figure 5 of yet another modified embodiment; Figure 8 is a sectional view similar to Figure 5 of a modified additional embodiment; Figure 9 is a sectional view similar to Figure 3 of yet another modified embodiment; Figure 10 is a schematic view showing the laser writing apparatus for forming a security article according to a method of the invention; Figure 11 is a schematic view showing the laser writing apparatus for forming a security article according to another method; Figure 12 is a flow diagram of a preferred method according to the invention; and Figure 13 is a schematic view of the alternative laser writing apparatus. DETAILED DESCRIPTION OF THE INVENTION Figure 1 shows a laminated security article 10 formed of three layers of transparent polymeric material 11, 12, 13 and having an image 14 of various colors and alphanumeric information. With reference to Figure 2, each of the transparent layers 11, 12, 13 carries at least part of the image 14 formed in a primary or complementary color different from the other layers. Therefore, the first layer 11 can carry a part or parts of the image 14 formed in a first individual color 21 such as blue or cyan, the second layer 12 can carry a part or parts of the image 14 formed in the second color. 22 different, such as yellow, and the third layer 13 may carry a part or parts of the image 14 formed in a third third color 23, such as red or magenta. The transparent layers 11, 12 and 13 overlap with the parts of the image formed by the different colors 21, 22, and 23 in the layers 11, 12, and 13, superposed one on top of the other in such a way that in the article 10 of laminated complete security, the different colors 21, 22, and 23, combine to form the image 14 of various colors. As shown in Figure 2, the alphanumeric information 16 can be formed by printing ink 26, 27 and 28 applied to the respective layers 11, 12, 13. However, it will be appreciated that the alphanumeric information may be formed in other ways, for example, by stamping, and may be applied to only one or two of the transparent layers 11, 12, 13. The schematic section of Figure 3 shows a preferred way to form the security article of Figure 1. Each of the parts of the multi-color image 14 formed in different colors 21, 22, 23 is embedded in its layer 11, 12, 13 respective transparent polymer. This is preferably accomplished by incorporating a color forming material in each transparent polymeric layer 11, 12, 13 and irradiating each layer with laser radiation of a particular wavelength to form the required parts or portions of the image 14 in color 21, 22, 23 respectively for each layer 11, 12, 13. A first lamination layer 31 is applied between the first and second layers 11, 12 and a second lamination layer 32 is applied between the second and third layers 12, 13 Transparent The lamination layers 31, 32 are preferably formed of a low melting point polymer or heat sensitive and / or pressure sensitive adhesives. The transparent layers 11, 12, 13 can then be laminated together by applying heat and / or pressure. As shown in Figure 3, the first lamination layer 31 is provided on the upper surface of the layer 11 and the second lamination layer 32 is provided on the lower surface of the layer 13. However, it will be appreciated that the layers 31 and 32, lamination can be provided on the lower and upper surfaces of the second transparent layer 12. Figure 4 shows a modified embodiment of a security article 40 which is similar to that of Figure 3 and similar reference numbers have been applied to the corresponding parts. Article 40 differs from that of Figure 1 in that it includes a fourth layer of polymeric material 41 which carries portions 44 of the image of various colors formed in a dark color, such as black. The dark parts of the image provide more depth and definition to the multi-color image formed by the parts of the image of various colors formed in the colors 21, 22 and 23 primary or secondary in the other transparent layers 11, 12 and 13. The fourth polymer layer 41 is laminated with the first transparent polymer layer 11 by a third lamination layer 43 provided between the first and fourth polymer layers 11 and 41. As shown in Figure 4, the third lamination layer 43 is provided on the lower surface of the first polymeric layer 11, but could equally be applied on the upper surface of the fourth polymeric layer 41. The security article 40 also incorporates additional information, such as alphanumeric information 46. Figure 4 shows the alphanumeric information 46 provided on the fourth polymer layer 41, but it will be appreciated that the alphanumeric information may be provided on some or all of the other layers 11, 12, 13 or 41. the alphanumeric information 46 and the parts 44 dark of the image can be embedded in the polymeric layer 41 by incorporating a color-forming material in the polymeric layer 41, which produces a dark color, such as black, when irradiated with laser radiation of a particular wavelength. Alternatively, the alphanumeric information 46 can be formed on the polymeric layer 46 by printing or other methods. The fourth polymer layer 41 can be formed of a transparent polymeric material when it is desired to produce a security article with a multi-color image that is visible from both sides. Alternatively, the fourth polymer layer 41 may be formed of a substantially opaque material, preferably white or a light color. In this case, the fourth opaque layer provides a contrast background to the multi-color image, which can improve its appearance. In this case, however, the multi-color image is visible only in reflection from one side of the security document. In a modified embodiment, the fourth layer 41 can be formed into a transparent polymeric material with one or more opacifying layers applied to its outer surface. Figure 5 shows another modified embodiment of a security article 50 which is similar to that of Figure 5 with corresponding reference numbers applied to the corresponding parts. The security article 50 differs from that of Figure 3 in that it includes additional images 51, 52 printed with optically variable inks on the first and second transparent layers 11, 12. Examples of optically variable inks, which may be used include pearl luster pigments sold by Merck under its IRIDION trademark and optically variable inks which exhibit a different color change when viewed at different angles, such pigments are sold by SICPA under its registered trademark OVI. As shown in Figure 5, the images 51, 52 printed with optically variable inks are provided in different laterally spaced locations on the first and second transparent layers 11, 12 and can overlap partially with each other and / or with the parts 21, 22 of the multi-color image embedded in the layers 11 and 12. The images 51, 52 provide additional security for the article 50 since, if a person attempts to spoil the document 50 by delamination, the optically variable images 51, 52 , which is provided on or adjacent to the lamination layers 31, 32 are cohesively broken, and the personalized information provided by the multi-color image formed by the color portions 21, 22, 23 embedded in the transparent layers 11, 12, 13 it is still present. Figure 6 shows a modified additional embodiment of a security article 60 similar to Figure 5 and corresponding reference numbers have been applied to the corresponding parts. The security article 60 of Figure 6 differs from that of Figure 5 insofar as to the extent that each of the layers 11, 12, 13 of transparent polymeric substrate has a transparent coating of polymeric material 61, 62, 63 in which the parts 21, 22, 23 of the multi-colored image 14 formed by the different colors are embedded, instead of in the layers 11, 12, 13 of polymer substrate per se. The transparent polymeric coatings 61, 62, 63 contain hidden color-forming pigments in such a way that the parts 21, 22, 23 of the multi-color image can be formed by irradiating the coatings with laser radiation of appropriate wavelengths. As shown in Figure 6, security article 60 also has a fourth polymeric layer 41 in a manner similar to security article 40. The fourth polymer layer 41 may be a transparent layer or an opaque layer as described with reference to Figure 4. Figure 6 shows the fourth polymer layer 41 laminated to the third upper layer 13 of transparent polymeric material by laminating the layer 43 in place to be laminated to the first lower layer 11, as shown in Figure 4. The security article 60 also includes images 51, 52 ethically variable, which can be printed with optically variable inks in a manner similar to article 50 security of Figure 5. Security article 60 may also include alphanumeric information (not shown), which may be printed on one or more of the layers, as described with reference to Figures 3 and 4. Figure 7 shows still another modified embodiment of a security document 70 which is similar to that of Figure 5 and corresponding reference numbers have been applied to the corresponding parts. The security document 70 differs from that of Figure 5 in that the part 22 of the multi-color image carried by the second layer 12 is embedded within a coating 72 of polymeric material on the second layer 12 instead of the second. layer 12 itself. The parts 21, 23 of the multi-color image carried by the first and third layers 11 and 13, are embedded or embedded within those layers. Parts 22 and 23 of the multi-color image formed in each layer are preferably formed by irradiating the layers with laser radiation of an appropriate wavelength, to reveal the colors in the latent color-forming pigments contained within the first and the third polymeric layers 11 and 13 and within the polymeric coating 73 on the second transparent polymeric layer 12. Figure 8 shows an additional modified embodiment of a security article 80 which is similar to that of Figure 5 and the corresponding reference numbers have been applied to the corresponding parts. The security article 80 differs from that of Figure 5 in that it includes a fourth layer 81 of transparent polymeric material which carries shadow images 82 of varying opacity. The shadow images 82 can be formed by applying opacifying coatings 84, 86 of varying thickness and / or opacity to the different locations of the upper surface of the fourth layer 81. The opacifying coatings can be formed from an opacifying white pigment, by example, titanium dioxide dispersed in a polymeric binder. As shown in Figure 8, shadow images 82 are formed by a first thin coating 84 applied on the entire surface of the fourth layer 81 and a second thin coating 86 applied to different regions of the fourth layer, for example, by Print. The fourth layer 81 is laminated to the first layer 11 by a lamination layer 83 applied to the lower surface of the first layer 81. The shadow images 82 provide additional security against the alteration by embedding them within the article 80 and if the article is altered, the shadow images 82 or part of the shadow image 82 can be broken after the delamination while the personalized information provided by the multi-colored image is still present.

Figure 9 shows still an additional modified embodiment of a security article 90 which is similar to that of Figure 3, and the corresponding reference numbers' have been applied to the corresponding parts. The security article 90 differs from that of Figure 3 in that it includes at least two portions of the image or partial images 91 and 92 applied to at least two of the transparent polymeric layers 11 and 12. The portions of the image or the partial images 91, 92 together form a recorded image from front to back when the partial images 91, 92 overlap one another in the register. Preferably, at least one of the partial images 91, 92 is embedded within or permanently applied to the transparent polymeric layer or layers 11, 12, for example, by etching or laser marking. Although both partial images 91, 92 are shown embeded or recorded in the respective layers 11, 12 in Figure 9, in a modified embodiment, one of the partial images 91 or 92 of the front-to-back registration image can be printed on its respective layer 11 or 12. In this case, if the security article 90 is altered, the printed partial images are destroyed by delamination, in such a way that a person who tries to fraudulently alter the document, must create a new partial image and place it in the exact register with the other 92 or 91 partial image embedded or laser marked on the other transparent polymeric layer 12 or 11. Although only two partial images 91, 92 are shown in Figure 9, it should be appreciated that the partial images can be provided in all of those transparent layers 11, 12, 13, which also contain the parts 21, 22 and 23 of the image pied. Again, the lamination layers 31 and 32 are provided between the transparent layers 11, 12, and 13 to laminate the transparent layers together with the parts 21, 22 and 23 in the register, to form the image of various colors and images 91, 92 in the record, to form the registration image from front to back. It should also be appreciated that other variations and modifications may be made to the embodiments of Figures 3 to 9. For example, those embodiments shown with only three polymer layers 11, 12, 13 may incorporate at least one additional, transparent or opaque polymer layer. , as described with reference to Figure 4. Also, a security article according to the invention may incorporate different combinations of some or all of the additional features of printed information, optically variable images, shadow images and forward registration images. backward, in addition to images of various colors formed by the colored parts 21, 22, 23 in the respective transparent layers 11, 12, 13. Figure 10 shows a method for forming a security article according to the invention. In Figure 10, a security article 100 comprises a first layer 101 of transparent polymeric material containing a laser-sensitive color-forming material and a second layer 102 of transparent polymer material containing a second laser-sensitive color-forming material. The two layers 101 and 102 are laminated together by a lamination layer 103. A multi-color image 104 can be formed in security article 100 by first exposing the first layer 101 to a laser beam 105 of a particular wavelength required to reveal the first color-forming material in the first layer 101 to form the portions 106 of the multi-color image in a first color (e.g., red or magenta) . The laser beam 105 is generated from a laser source 107 and preferably a deflection beam unit 108 is used to direct the laser beam 105 onto the first layer 101 to write the parts 106 of the multi-color image in the first color. Then, security article 100 can be flipped in such a way that the second layer 102 is facing the laser apparatus in such a way that the parts 109 of the multi-color image in the second color (e.g., blue or cyano) can be written to the second transparent layer 102. Although it is possible to form a multi-color image of only two transparent layers containing the parts of the image in two different primary or complementary colors, if a third color is required (eg yellow or green), a third layer can be provided transparent polymer containing a third color-forming material, in which the parts of the image can be written in the third colors using the laser apparatus. The third transparent layer can be laminated on either side of the security article 100 formed by the first and second transparent layers 101, 102 either before or after the parts of the image are written in the third color by the laser beam. As alternatives to the laser marking process which uses the beam deflection technique, a masking technique or a dot matrix technique can be used. For variable data such as personalization, beam deflection and dot matrix techniques are more appropriate. The main advantages are due to the high degree of flexibility associated with beam deflection or two rotating mirrors. A change in dialing is possible simply by changing the computer program. In this process, the marking is carried out in a similar way to a plotter, however, with much greater speed. The advantages of variable laser marking data are that they are free of contact which results in little or no mechanical wear. They are free of ink, without expensive consumables and have no problems with volatile inks. And you also have a high speed dialing. Up to 6000 markings per minute can be obtained with a pulsed C02 laser and up to 3000 mm / sec of markings can be obtained with a Nd: YAG laser. The desired fidelity and resolution of the marked image is a compromise between speed, laser energy and wavelength and the interaction of these with the material. In the case of a 1064 nm? D: YAG laser the resolution may be in the order of a dot size of 10 μm (approximately 2500 dots per inch are possible in an image). The principle of color formation with Merck pigments is based on the carbonization and surface formation between Ti02 coated mica pigments, polymer and laser energy. For lasers with shorter wavelengths such as the? D: YAG laser at 355 nm the resolution of the image could be even higher. The CIBA color-forming additives could be used in the transparent polymer layers to create a color change at such a wavelength. The laser energy removes a proton from the hydrocarbon molecule which reacts with a latent color former to produce a color with the specific length of the light. With reference to Figures 11 and 12, a laser writing apparatus and the method for forming a security article 110 according to the invention are schematically illustrated. The security article 110 in Figure 11 is in the form of a booklet which has three transparent layers of material 111, 112, and 113 polymeric, each one forming a page or sheet of the booklet. In the case of a passport, which is required to contain personalized information, for example in the form of a multi-color photograph, the transparent layers 111, 112 and 113 can be sewn directly into the booklet before personalization. The laser writing apparatus in Figure 11 is similar to that of Figure 10 in that it comprises a laser source 117 and a beam deflecting unit 118 for directing a laser beam 115 of a particular wavelength over the layers. 111, 112 and 113 of transparent polymeric material, each of which contains a laser-sensitive color-forming material in a different color. For example, the first layer 111 could contain a first latent color forming pigment which forms a red or magenta color when exposed to laser radiation of a particular wavelength, the second layer could contain a blue color forming pigment or cyan and the third layer could contain a green or yellow color pigment. A preferred method for forming the security article 110 with a customized multi-color image is illustrated schematically in the block diagram of Figure 12. First, the customized multi-color image to be provided is scanned (Step 120) in high resolution. in Article 110, for example, by means of an appropriate computer image creation package. Next, the image is analyzed by the data management program (Step 121) to separate the multi-color image into the individual components of primary or complementary colors corresponding to the colors of the color-forming pigments in layers 111, 112 and 113. The booklet containing the transparent layers of polymeric films 111, 112, 113 is then fed to the laser writing apparatus 117, 118 (Step 122) and the laser writing program is used to control the apparatus 117, 118, for Write the parts of the image 114 of various colors in the first color in the transparent layer 111 (Step 123).

After the parts of the image 114 have been written in the first color, the next page or sheet of the booklet formed by the second layer 112 is turned over and placed in the laser writing apparatus, such that the laser beam 115 it can be used to write the parts of the image 114 in the second color of the color forming material in the second layer 112 (Step 124). A laser blocking sheet (not shown) can be placed between the first and second layers 111 and 112 to prevent the laser from striking through the first layer 111 when the parts of the image 114 are being written on the second layer 112. The page or sheet of the booklet formed by the third transparent layer 113 is then turned over and placed on the laser writing apparatus and Step 124 is repeated to write the parts of the image 114 into the third color of the forming material of color in the third layer 113. Again, a laser blocking sheet can be placed between the second and third layers 112, 113, to prevent the laser from striking through the second layer when the parts of the image are being written in the third layer. Security article 110 may include an optional fourth layer (not shown) containing a laser-sensitive color-forming pigment, which produces a dark color, e.g., black, when exposed to laser radiation of a length of particular wave. Again, step 124 may be repeated in such a manner that the laser writing apparatus writes the parts of the image in dark color to provide more depth and definition to the multi-color image. Each of the parts of the image 114 of various colors in the different colors of the different layers, may be formed into points, lines or crosses, or a combination thereof. The size and frequency of the structural pattern can be varied. In some cases, interference effects may be created, such as interference fringes, although in other cases interference effects should be avoided. The multi-color image should be constructed from a specific pattern or grid, such as a stochastic reticle. Such a stochastic grid could be displayed under magnification (for example x 10) and acts as a secondary level security feature. You can also select the color-forming materials in the transparent layers in such a way that additive colors are used to produce other colors in the multi-color image. For example, layers containing the colors green and blue could be used to create lines and cyan dots. One or more of the transparent layers 111, 112, 113 may also include alphanumeric information 116, which may be applied to the layer or layers by printing and / or by laser writing. Other security features may be applied to layers 111, 112, 113, such as shadow images, images formed with optically variable inks, and front-to-back recording images, as described with reference to Figures 5 through 9. When all parts of the multi-color image have been written in the different colors in the different layers 111, 112, 113, the booklet 110 formed by the layers is then passed through a supply mechanism to the rolling apparatus (Step 125) where the transparent layers 111, 112, 113 which contain the parts of the image of various colors in the different colors are laminated together (Step 126), for example, by applying heat and / or pressure, to form the laminated security article, which it can be a passport data page or an identity card. For this purpose, lamination layers of low melting point polymers between the transparent layers 111, 112, 113 can be applied as described with reference to Figures 3 to 9. The rolling temperature is selected in such a way that the temperature is greater than the melting point of the lamination polymer but lower than the melting point of the polymeric material of the transparent layers 111, 112, 113.

Figure 13 shows an alternative laser apparatus for creating images of various colors in a security article. Instead of the deflector 118 of the beam of Figure 11, the laser beam 125 is reflected off two rotating scanning mirrors 127, 128 and is focused by a lens 129 on a transparent polymeric layer 121 containing a first color-forming material. laser-sensitive to write the parts of a multi-colored image 124 in the layer 121. The process is then repeated for at least one other transparent layer containing a different laser-sensitive color-forming material, in a manner similar to that described with reference to Figures 12 and 13. The laser beam 125 can also be used to write alphanumeric information 126 into one or more of the transparent layers 121 as shown in Figure 13. From the description above, it will be apparent that the present invention provides various forms of security articles with images of various colors, of obvious alteration or falsification, and the methods for manufacturing such ar security items. Clear alteration images can not be removed without an indication of tampering. The images can not be extracted by leaching with solvents or other chemicals and are resistant to abrasion. Most custom documents are based on an opaque substrate where the image is visible only from one side. Images of various colors in security articles according to the first aspect of the invention can be observed from both sides, which makes it easier to identify any alteration. Even if the multilayer security article is delaminated, the images are still imbedded in the core polymer. In addition, laser-embossed images can be combined with other printed security features. It will be appreciated that various modifications and alterations can be made to the preferred embodiments described above without departing from the scope and spirit of the invention.

Claims (57)

1. CLAIMS 1. An article of security that has a multi-colored or multi-colored image and which comprises: a first layer of transparent polymer material bearing parts of an image formed in a first color; at least one other layer of transparent polymer material carrying portions of said image formed in at least one different color; characterized in that the layers are laminated together with the parts of the image formed in the first one and the different colors superposed one on top of the other, in such a way that the colors combine to form a multi-colored image in the laminated safety article, the Multi-color image that can be seen from both sides of the security article. A security article according to claim 1, characterized in that the multicolored or multicolored image is formed by the first and second superimposed portions of the image in different colors, in the first and second layers. 3. A security article according to claim 2, characterized in that it further comprises a third layer of transparent polymer material carrying parts of an image formed in a third color. 4. A security article according to any of claims 1 to 3, characterized in that the colors of the image formed in the layers are primary or complementary colors. 5. A security article according to any of claims 1 to 4 characterized in that it comprises an additional layer of transparent polymeric material that carries parts of the image formed in a dark color, to provide more depth and definition to the image of various colors . 6. A security article according to claim 5, characterized in that the dark color is black. 7. A security article according to any of claims 1 to 6, characterized in that the parts of the image formed in the layers are indelible. 8. A security article according to claim 7, characterized in that the parts of the image formed by the different colors are formed in the different layers by laser marking. 9. A security article according to claim 7 or claim 8, characterized in that at least one of the layers comprises a transparent polymeric film or substrate in which a respective part of the image is imbibed. 10. A security article according to claim 7 or claim 8, characterized in that at least one of the layers comprises a transparent polymeric substrate having a transparent polymeric film or coating on at least one surface, into which a part is embedded. respective of the image. 11. A security article according to any of claims 8 to 10, characterized in that the parts of the image formed in different colors in the respective layers, are embedded inside the layers using layers of transparent polymeric material each containing a latent color forming pigment, which is revealed by exposure to laser radiation. 12. A security article according to any of the preceding claims, characterized in that at least one of the layers includes alphanumeric information 13. An article of security according to any of the preceding claims, characterized in that it also includes some or more of the following: shadow images, or images printed with optically variable inks, or registration images from front to back 14. A security article according to any of the preceding claims, characterized in that the security article is adapted to be secured to another article 15. A security article according to any of the preceding claims, characterized in that the multi-color image is a photograph of the article holder 16. A security article according to claim 15, characterized in that the article is part of a passport or other identification document. 17. A passport incorporating a security article according to claim 15, characterized in that the article forms part of at least one page of the passport in such a way that the photograph of the passport holder can be seen from both sides of the page. 18. A passport according to claim 17, characterized in that the passport is a booklet which includes at least one opaque page next to the page that incorporates the photograph. 19. A method for manufacturing a security article having a multi-color image, characterized in that the method comprises: providing a first layer of transparent polymeric material; providing at least one other layer of transparent polymeric material; forming the parts of an image in a first color in or on the first layer; forming the parts of said image in at least one different color in or on said at least one other layer; and laminating the layers together to form a laminated security article; where, in the laminated safety article, the parts of the image formed in the first and the different colors are superposed on one another in such a way that the colors combine to form a multi-colored image which can be seen from both sides of the laminated safety article. 20. A method according to claim 19, characterized in that the multi-color image is formed by the first and second superimposed parts of the image in different colors in the first and second layers. 21. A method according to claim 20, characterized in that the first and second layers are laminated before the parts of the image are formed in the different colors in the respective layers. 22. A method according to claim 20, characterized in that the first and second layers are laminated after the parts of the image are formed in the different colors in the respective layers. 23. A method according to any of claims 19 to 22, the method characterized in that it further comprises the steps of: providing a third layer of transparent polymeric material; and forming the parts of the image in a third color in or on the third layer. A method according to any of claims 19 to 23, characterized in that the colors of the image formed in the different layers are primary or complementary colors. 25. A method according to any of claims 19 to 24, the method is characterized in that it further comprises the steps of: providing an additional layer of transparent polymeric material; and forming the parts of an image in a dark color in or on the additional layer whereby the dark color provides more depth and definition to the image of various colors. 26. A method according to claim 25, characterized in that the dark color is black. 27. A method according to any of claims 19 to 26, characterized in that the parts of the image formed in the different colors are applied to the different layers by a laser marking process. A method according to claim 27, characterized in that the image to be formed in the laminated security article is scanned by a program in a digital image and separated into the individual primary or complementary colors before the laser marking process. . 29. A method according to claim 27 or 28, characterized in that the laser marking process includes the steps of: applying the parts of the image formed in the first color to the first transparent layer; applying the parts of the image formed in the second color to the second transparent layer; and optionally applying the parts of the image formed in other different colors to the third and the subsequent layers. 30. A method according to any of claims 19 to 22, characterized in that the different parts of the image in the different colors are embedded within the respective layers of transparent polymeric material. 31. An evident tampering or tampering safety article, characterized in that it has a multi-color image and which comprises: a first layer of transparent polymer material containing portions of an image formed in a first color embedded within said layer; at least one other layer of transparent polymer material containing portions of said image formed in at least one different color, embedded within said at least one other layer; where the layers are laminated together with the parts of the image formed in the first and the different colors superimposed on each other, whereby colors are combined to form a multi-colored image in the laminated security article. 32. A tamper evident tampering security article according to claim 31, characterized in that at least one of the layers comprises a transparent polymeric film or substrate into which a respective part of the image is embedded. 33. A tamper evident tampering article according to claim 31, characterized in that at least one of the layers comprises a transparent polymeric substrate having a transparent polymeric film or coating on at least one surface, in which a respective part of the color image is embedded. 34. A tamper evident tampering security article according to any one of claims 31 to 33, characterized in that the parts of the image formed in the different colors in the respective layers are embedded within the layers using layers of material transparent polymer each containing a respective color-forming pigment, which forms a color marking when exposed to laser radiation. 35. An evident tampering or tampering safety article according to claim 34, characterized in that the thickness of each layer of polymeric material falls substantially within the range of about 20 microns to about 200 microns. 36. An evident tampering or tamper evident security article according to claim 34 or claim 35, characterized in that a thin layer of a low melting point polymer is co-extruded on one or both sides of a film of polymeric base to form at least one of the layers in which a color-forming material is provided. 37. An evident tampering or tampering safety article according to claim 36, characterized in that, the color forming material is provided in the polymeric base film. 38. An evident tampering or tampering safety article according to claim 36, characterized in that, the color forming material is provided in the co-extruded layer. 39. An evident tampering or tampering safety article according to any one of claims 36 to 38, characterized in that the thin co-extruded layer has a thickness that falls substantially within the range of about 2 microns to about 50 microns. 40. An evident tampering or tamper evident security article according to any one of claims 34 to 39, characterized in that the co-extruded layer is formed of either metallocene, polyethylene, random copolymers or ethylene, butylene or propylene terpolymers. . 41. An evident tampering or tampering safety article according to any one of claims 34 to 40, characterized in that the latent color-forming pigments are present in the layers of transparent polymeric material in a concentration that falls substantially within the range of about 0.2% to about 0.5% by weight of the polymeric material. 42. An obvious alteration or falsification security article according to any of claims 31 to 41, characterized in that the article is adapted for its attachment to another article. 43. An evident tampering or tampering safety article according to any one of claims 31 to 42, characterized in that it also includes an opaque layer on one side of the transparent layers containing the parts of the image in different colors, such that the multi-colored image in the laminated security article is only visible in reflection from one side of the article. 44. An evident tampering or tampering security article according to any of claims 31 to 43, characterized in that at least one of the layers includes printed information. 45. A tamper evident tampering security article according to any of claims 31 to 44, characterized in that it further includes one or more of: shadow images printed; or images printed with optically variable inks; or registration images from front to back. 46. A method for manufacturing a tamper evident security article having a multi-color image, characterized in that the method comprises: providing a first layer of transparent polymer material containing a first latent color-forming material; providing at least one other layer of transparent polymer material containing a different latent color-forming material; forming the parts of an image in a first color by exposing the at least one other layer to the laser radiation to reveal the latent color forming material in the first layer; forming the parts of the image in a different color by exposing said at least one other layer to laser radiation to reveal the different latent color forming material in said at least one other layer; and laminating the layers together with the parts of the image formed in the first and the different colors superposed one on top of the other, whereby the colors are combined to form the multi-colored image in the laminated security document. 47. A method according to claim 42, characterized in that the laser radiation causes the marking of color by the development of the latent color forming materials, without causing the fusion or abrasion of the polymeric materials. 48. A method according to claim 46 or claim 47, characterized in that the layers of polymeric material containing the latent color-forming pigments are produced by pre-mixing a batch of polymer which is mixed with the latent color-forming material. respective. 49. A method according to any of claims 46 to 48, characterized in that the laser radiation is provided by one of the following: a beam deflection technique; a vector process; a masking technique; or a dot matrix technique. 50. A method according to any of claims 46 to 49, characterized in that a lamination layer is applied between the adjacent layers of transparent polymeric material containing the color-forming material. 51. A method according to claim 50, characterized in that the lamination layer is formed of a low melting point polymer or a heat and / or pressure sensitive adhesive is used to laminate the layers of polymeric material together. 52. A method according to some of claims 46 to 51, characterized in that the colors formed by the latent color forming materials in the first and the other layers are primary or complementary colors. 53. A method according to claim 52, characterized in that it includes the steps of: providing an additional layer of transparent polymeric material containing a dark colored forming material; forming the parts of the image in dark color by exposing said additional layer to laser radiation; and laminating said additional layer with the other layers with the parts of the image formed in dark color superimposed on the parts of the image formed in the different colors to provide more depth and definition to the image of various colors. 54. A method according to claim 52 or claim 53, characterized in that the image to be formed in the security article of tamper evident or falsified is scanned by a computer program to a digital image and separated into the primary color components or secondary corresponding to the color-forming materials in the layers, and laser writing is used to separate the color components to reveal the color-forming materials in the respective layers. 55. A method according to any of claims 46 to 54, characterized in that it includes the steps of applying alphanumeric information to at least one of said layers. 56. A method according to any of claims 46 to 54, characterized in that it further includes the step of providing at least one security feature on at least one of the layers, the security feature that is destroyed or damaged when it is delaminated. the security article. 57. A method according to claim 56, characterized in that, the at least one security feature comprises one or more of the following: a shadow image: an image printed with optically variable inks; and a registration image from front to back.