1. Field
The present disclosure is generally related to security marks on documents.
2. Description of Related Art
Security marks, barcodes, and glyphs that are considered invisible to the eye are well known, and are used for many applications, such as tracking workflow and job security, high-security tickets, high-value documents and anti-counterfeiting applications. Some of these security marks are made with materials (e.g., ink or toner) which have almost no absorption in the visible spectrum of light, but have significant absorption in non-visible parts of the electromagnetic spectrum (i.e., to the human eye), such as ultraviolet (UV) or infrared (IR) radiation. Other marks rely on fluorescence of the material under suitable light, such as UV radiation.
Some of these applications use approximately “colorless” rather than truly “invisible” inks or toners. Such colorless materials are commonly “clear” inks/toners, i.e., materials similar to other inks/toners used in the system, except that they are substantially free of any colorants such as pigments or dyes, which give the other inks/toners their characteristic color properties in the visible range. These clear inks/toners typically have refractive indices and surface characteristics that are different from the substrate. In many marking technologies, such as xerography, lithography, flexography, and UV inkjet and solid inkjet technologies, the inks/toners exist in one or more layers on top of the paper. Consequently, the clear inks/toners can be detected by human observers, even without any special equipment, due to the gloss difference between the applied ink/toner and the bare substrate. For example, in some cases, when one alters the viewing angle of a page, the gloss of the invisible mark can be seen. For some applications this may not matter, but where truly invisible security marks are required, these materials are inadequate.
This gloss differential is a problem for such materials. In some cases, it has been possible to match closely the gloss of an ink or toner with a gloss of a particular substrate (e.g., uncoated paper) that the ink/toner is applied on. However, even though it may be possible to match the gloss of a particular ink to one particular substrate, developing and using a different ink/toner for each substrate is inconvenient and not necessarily feasible. For example, the ink/toner selected most likely will not match the gloss on other papers or substrates (e.g., gloss coated paper). Generally, the ink or toner can have a gloss appearance very different from that of the default paper or other papers that may be used in the printer.
Additionally, the above matching approach would require different inks or toners to be made (and then installed in the printer) for each substrate. This is also not a practical and/or feasible solution.
Thus, although attempts have been made to match the gloss of inks and toners to that of the substrate, such an approach has limited success.
One aspect of the disclosure provides a composite security element on a substrate. The composite security element includes a first pattern mark and a second pattern mark. The first pattern mark is applied using a first marking material and the second pattern mark is applied using a second marking material. The first pattern mark and the second pattern mark are indistinguishable from each other under radiation of wavelengths within the visible spectrum and distinguishable from each other under radiation of at least some wavelengths outside the visible spectrum.
Another aspect of the disclosure provides a composite security element on a substrate. The composite security element includes a first pattern mark in an active marking material that is reactive to radiation of at least some wavelengths outside a visible spectrum; and a second pattern mark in a passive marking material that is unreactive to radiation of wavelengths outside the visible spectrum. The first pattern mark is distinguishable from the second pattern mark by a naked human eye or by a machine when exposed to radiation of wavelengths outside the visible spectrum and indistinguishable from the second pattern mark by at least the naked human eye when exposed to radiation of wavelengths within the visible spectrum.
Yet another aspect of the disclosure provides a method for applying a composite security element to a substrate using a printing apparatus. The printing apparatus has at least one marking material applicator. The composite security element includes a first pattern mark and a second pattern mark. The method includes:
marking the first pattern mark in a first marking material on the substrate using the at least one marking material applicator; and
marking the second pattern mark in a second marking material on the substrate using the at least one marking material applicator.
The marking of the second pattern mark renders the first pattern mark and the second pattern mark indistinguishable from one another in radiation of wavelengths within the visible spectrum.
Other features and advantages of the present disclosure will become apparent from the following detailed description, the accompanying drawings, and the appended claims.
This disclosure proposes the use of two marking materials (e.g., clear or substantially colorless ink or toners) for digitally watermarking (e.g., for security and/or authentication purposes) a security mark on a substrate with one material, and rendering the security mark substantially indistinguishable or unreadable in visible light (by the naked human eye) by the marking of the other material. Although reference may be made to marking materials as one or more inks throughout this disclosure, it should be understood that toners or other materials for marking may be used for the herein described composite security element, and the method for marking the same.
For purposes of simplicity only, the term “security mark” is used throughout this disclosure to describe a mark or an overcoat that is applied to a substrate (or document). A “security mark” is defined as an indicating mark that is used for identification or authentication purposes, and in some cases may include any one or number of shapes and/or patterns such as text, number(s), a logo, picture(s), barcode(s), glyph(s), and/or the like. The security mark may comprise a predetermined or random pattern. Throughout this disclosure, the term “security mark” is used interchangeably with “first pattern mark” when referencing its application to a substrate. A substrate can comprise any number of objects or materials including, but not limited to, paper, document(s), currency, tickets, credit cards, licenses, coupons, packaging, and the like. The substrate can receive any size or shape security mark, and be provided in any number of locations (e.g., on a front or back surface). The security mark—or first pattern mark—is part of the herein disclosed “composite security element.” As further described below, a composite security element comprises a plurality of marks (first and second pattern marks) applied to a substrate using two or more marking materials. The second pattern mark may comprise a predetermined or random pattern. As further described below, the second pattern mark renders the first pattern mark indistinguishable in visible light such that non-visible light (e.g., UV or IR light) must be used for viewing or sensing the security mark.
The composite security elements and/or security marks in the illustrated embodiments are shown in dashed lines in the provided Figures for illustrative purposes only, because, as further described in some embodiments below, the mark(s) is/are printed in clear or colorless ink, and thus may not be readily distinguishable from the substrate. In some embodiments, the marking materials and substrate have substantially similar gloss characteristics. In some embodiments, the element(s) or mark(s) are substantially invisible.
No matter its size, the composite security element comprises a first pattern mark and a second pattern mark. In radiation of wavelengths within the visible spectrum (i.e., under visible light), the first pattern mark and the second pattern mark are indistinguishable from each other. The visible spectrum of light, also referred to as “visible light” throughout this disclosure, is defined by the electromagnetic spectrum and comprises electromagnetic radiation of wavelengths that are in a range from about 380 or 400 nanometers (nm) to about 760 or 780 nm. However, under radiation of wavelengths outside the visible spectrum, or “non-visible light”, the first pattern mark and the second pattern mark are distinguishable from each other. For example, the composite security mark may be illuminated by ultraviolet light or infrared light (which are both regions of the electromagnetic spectrum which are outside the visible spectrum). Generally, ultraviolet (UV) light is electromagnetic radiation with wavelengths shorter than that of visible light, but longer than X-rays, in the range about 10 nm to about 400 nm. Infrared (IR) light is electromagnetic radiation with wavelengths between about 0.7 and about 300 micrometers. IR wavelengths are longer than that of visible light, but shorter than that of certain radiation microwaves.
In accordance with an embodiment, the first pattern mark (i.e., security mark) and second pattern mark are configured to be substantially invisible to at least the naked human eye when the composite security element is illuminated by light having wavelengths within the visible spectrum. The “naked human eye” refers to human visual perception that is unaided by a light-discerning or light-collecting optical device. In some embodiments, the first pattern mark and second pattern mark may be configured to be substantially invisible to a machine when the composite security element is illuminated by visible light. The “machine” refers to a device that is used to distinguish or discern a security mark. In an embodiment, a machine (e.g., a scanner) may include a light source. In another embodiment, a machine (e.g., a camera) may be aided by a light source (e.g., laser or radiation source).
The first pattern mark is applied using a first marking material, and the second pattern mark is applied using a second marking material. In this disclosure, the first pattern mark of the composite security element may be described as being marked or applied using an “active” marking material, i.e., a marking material that is configured to substantially react to radiation having at least some wavelengths outside a visible spectrum, such that the first pattern mark is distinguishable by the human eye or by a machine when exposed to such radiation. Also, in this disclosure, the second pattern mark of the composite security element may be described as being marked or applied using a “passive” marking material, i.e., a marking material that is substantially unreactive to the radiation having wavelengths outside a visible spectrum. That is, when non-visible light (i.e., light or radiation having wavelengths outside a visible spectrum) such as UV or IR light is used to illuminate the composite security element, for example, the pattern mark formed in the passive marking material will not react, and will not be readily distinguishable to the naked human eye (or, in some instances, to a machine). In some cases, the second pattern mark may be substantially invisible in both visible and non-visible light.
In an embodiment, the first (active) marking material is configured to have greater absorption in radiation of at least some wavelengths outside the visible spectrum than that of the substrate. Thus, the first pattern mark may additionally be distinguishable from the substrate under non-visible light.
Referring back to the illustrated embodiment of
In yet another embodiment, the second pattern mark is provided in a predetermined pattern that is sufficient to render the first pattern mark indistinguishable in visible light. For example, in an embodiment, the pattern of the second pattern mark may be based on the pattern of the first pattern mark.
In another embodiment, the second pattern mark can be a random or sporadic pattern which obscures the legibility of the first pattern mark. For example, the second pattern mark may comprise a random or non-random pattern that camouflages the first pattern mark, which may or may not cover and/or overlap or intertwine with the first pattern mark, the predetermined area, and/or a negative space. Accordingly, it should be understood that the second pattern mark need not to be contained to a predetermined area and/or a predetermined pattern for its application.
In any case, the second pattern mark hides or scrambles the appearance of first pattern mark so that it is indistinguishable in visible light. That is, when composite security element 104 and predetermined area 105 are viewed in visible light by the naked human eye, at least the first and second security marks 110 and 112 are indistinguishable from each other. In an embodiment, substantially the entire composite security element 104 is indistinguishable, not recognizable, and/or undetectable, as shown in
Radiation source 150 may be a part of a printing apparatus, such as one of the apparatuses 300 in
In addition to the above-noted features, in an embodiment, the first pattern mark and the second pattern mark are colorless. Both of the marking materials used for application of the composite security element on the substrate (i.e., the active and passive materials) may be at least colorless to light having wavelengths within the visible spectrum. As used throughout this disclosure, a “colorless” marking material is defined as a material that is substantially free of any colorants such as pigments or dyes, which give the other inks/toners their characteristic color properties in the visible range. For example, if the composite security element is used as an overcoat and applied over image data on the substrate (e.g., overcoats on ink based images and xerographic images), the colorless marking materials allows for printed image data to still be viewed through the composite security element. In an embodiment, the marking materials will be substantially colorless and the patterns will not be readily distinguishable or recognizable by at least a naked human eye (and in some instances, by a machine) in visible light.
Also, in an embodiment, the first pattern mark and the second pattern mark both are associated with a substantially similar gloss in at least light having wavelengths within the visible spectrum. Gloss is an optical property which is generally based on the interaction of visible light with physical characteristics of a surface (in this case, a surface of the marks). Some factors that affect gloss are: a refractive index of a material, and the roughness of the surface of the material. The roughness of the surface of the material may depend on processes for applying or treating the material (e.g., heat and/or fusing steps), and a roughness of a surface to which the material is applied. After application of the marking materials on the substrate, the first and second pattern marks will not be readily distinguishable to the at least the naked human eye because the gloss of each of the two marks is indistinguishable from each other when reflecting visible light (relative to the illumination angle). For example, as previously noted, one can alter the viewing angle of a substrate. “Viewing angle” refers to an angle measured with respect to a surface or plane of the substrate. In some cases, when one alters the viewing angle of a page or a substrate, the gloss of an invisible mark (i.e., gloss of the applied marking material) can be seen. With the application of two marking materials associated with a similar gloss to form first and second pattern marks on a substrate as described herein, the patterns are substantially or entirely indistinguishable from one another. For example, in an embodiment, when the first (active) marking material is applied in a positive space to form a first pattern mark, such as 110 in an area 105 as shown in
In an embodiment, the first and second pattern marks are both colorless and have similar gloss values. In an embodiment, the gloss of the pattern marks is substantially similar or the same as that of the substrate.
In some embodiments, the marking materials can have a gloss appearance that is different from that of a default paper or substrate used in a printing apparatus. Thus, there may be a possibility that the gloss of the first and second pattern marks may be visible at some viewing angle(s) because of gloss differential (i.e., because the gloss of the pattern marks is slightly or more different than the gloss of the substrate they are marked on). For example, the area for application (e.g., predetermined area 105) may be visibly detectable by the eye (with respect to the substrate's surface) when viewed at a certain angle. However, even if the area of the composite security element is visible based on a gloss differential as compared to the surface of the substrate it is marked on, the first pattern mark and/or second pattern mark would still be indistinguishable to the naked human eye, because the gloss of the marking materials would be substantially the same when viewed in light of the visible spectrum. Therefore, the pattern marks will not be readily distinguishable and/or viewable by at least the human eye, unless non-visible light is directed at the composite security mark.
The first and second marking materials may comprise a matte or a glossy finish on a substrate. In an embodiment, the finish of the marking materials for first and second pattern marks is based on a finish of the substrate they are marked on. The first and second marking materials can have any gloss value (e.g., as measured by a gloss meter) and are not meant to be limiting. For example, the TAPPI (Technical Association of the Paper and Pulp Industry) has a standard identified as T-480 which defines a 75 degree glossmeter geometry. In accordance with a non-limiting embodiment, the first and/or second marking materials have a gloss value which may be substantially identical when specified in TAPPI T-480 gloss units. In another embodiment, first and second marking materials may or may not have gloss values that are similar to that of the substrate.
In accordance with another embodiment of this disclosure, the gloss of the first and second pattern marks is substantially similar to a gloss of a surface of the substrate when viewed in light having wavelengths within the visible spectrum. When the surface of the substrate and the composite security element are both associated with a substantially similar gloss, substantially little or none of the composite security element or its patterns applied thereon are distinguishable in the visible spectrum by the naked human eye at substantially any angle. Even if the substrate were to be angled or tilted to one or more viewing angles, the substrate would have substantially the same gloss across its entire surface because the substrate and marking materials have substantially the same gloss characteristics.
The substrate on which the marking materials/pattern marks are applied may comprise a matte or a glossy surface and is not meant to be limiting.
The application and/or area (e.g., area 105) of a substrate in which the first and second marking materials are applied are not meant to be limiting. Also, the size, shape, and/or patterns of first and second pattern marks are not meant to be limited to the illustrated embodiments. For example, as noted previously, the pattern marks may be in the form of text (words), numbers, symbols, barcodes, glyphs, and the like.
In an embodiment, the size of the second pattern mark may be slightly or significantly larger than the size of the first pattern mark. In another embodiment, the second pattern mark may be substantially similar in size to the first pattern mark (e.g., to just cover the first pattern mark).
In another embodiment, when the first pattern mark 118 comprises an area that is smaller than the predetermined area 116, as shown in
In yet another embodiment, the first pattern mark 118 may be marked or applied to cover part and/or substantially the entire predetermined area 116 of the substrate 114, and the second pattern mark 121 may be marked or applied to a part or whole of the remaining uncovered (i.e., not marked by the first marking material) surface of the substrate 114. In an embodiment, the second pattern mark is provided over substantially an entire surface of the substrate, including marking over the first pattern mark.
In another embodiment, the second pattern mark 130 is provided over substantially an entire surface of the substrate 122, e.g., in the form of an overcoat, no matter the size of the predetermined area for marking the first pattern mark (the security mark). For example, the predetermined area 126 may be sized for marking the first pattern mark.
In yet another embodiment in accordance with this disclosure, a composite security element may be applied to a surface of a page, substrate, or document using previous and/or known methods and marking materials. Then the surface of the substrate is covered—i.e., both the composite security element and any other remaining areas—with a second pattern mark by application of second (passive) marking materials as described herein. In a similar manner as described above, there is no differential-gloss issue on such a substrate. The security mark (or watermark, or first pattern mark) remains substantially indistinguishable (i.e., invisible) under normal visible light, but at least the first pattern mark can be distinguishable from the second pattern mark when UV or IR light is applied.
In either
The method and composite security element embodiments as disclosed herein substantially reduce and/or eliminate known problems in the art related to gloss differentials (e.g., related to a visible differential between the mark and the substrate, and/or related to a visible differential in marking materials used for the security mark, when viewed at a viewing angle).
This disclosure also reduces and/or eliminates any need to match the gloss of the marking material(s) to the substrate or paper, as in previous works. This is because the mark which may be used for security or authentication, i.e., the first pattern mark, is indistinguishable from the second pattern mark (no matter its application) by the naked human eye. The first pattern mark is only distinguishable and/or visible to the human eye and/or machine under an application of radiation having at least some wavelengths outside the visible spectrum. Additionally, because the first pattern mark and second pattern mark are associated with substantially similar gloss values (no matter the size of the predetermined area), there is substantially no differential gloss between them in light having wavelengths within the visible spectrum. Therefore, the pattern marks are indistinguishable from each other in visible light by looking at their specular gloss. The first pattern mark and second pattern mark can not be readily distinguishable from one another at any viewing angle, without application of radiation having at least some wavelengths outside the visible spectrum, such as UV or IR radiation.
The method 200 as illustrated comprises receiving a substrate for applying or marking with at least first (active) and second (passive) marking materials, as shown in block 202. In an embodiment, the substrate may comprise printed information thereon when received. In an embodiment, printed information may be provided or marked with (consecutively or concurrently) the application of the active and passive marking materials. As previously noted, the type of substrate to which the active and passive marking materials is applied should not be limiting.
After the substrate is received at 202, a first pattern mark is marked at block 204 in an active marking material on the substrate using at least one marking material applicator of the printing apparatus. The active marking material may comprise a fluorescent, a luminescent, a phosphorescent, or a scintillating material, for example, or a material that has absorption characteristics in the non-visible wavelengths which are significantly higher than that of the second marking material and/or substrate. Then, a second pattern mark is marked at block 206 in a passive marking material on the substrate using the at least one marking material applicator of the printing apparatus. In an embodiment, both the active marking material and the passive marking material are colorless to radiation having wavelengths within the visible spectrum. Also, both the first pattern mark and the second pattern mark are associated with a substantially similar gloss when reflecting light having wavelengths in the visible spectrum of light. Then, the substrate may be output, as shown at block 208.
In an embodiment, the gloss of the first and second pattern marks is substantially similar to a gloss of the substrate they are applied thereto in light of the visible spectrum.
The method 200 is not meant to be limiting and may comprise additional or subsequent steps other than those shown in
In an embodiment, the marking of the second pattern mark at block 206 comprises rendering the first pattern mark and the second pattern mark as indistinguishable from one another in radiation of wavelengths within the visible spectrum. In an embodiment, this may include marking the second pattern mark in a space at least around the first pattern mark.
In an embodiment, the passive marking material and the active marking material are arranged side-by-side. For example, the first and second patterns may be applied to form a single layer of clear or colorless ink on the substrate. In another embodiment, the marking at block 206 comprises marking the second pattern mark in or over at least the predetermined area of the substrate. In yet another embodiment, the marking at block 206 comprises marking the second pattern mark over substantially an entire surface of the substrate. Such exemplary embodiments have been shown and described above with respect to
Moreover, it is noted that the order of application of the first and second marking materials is not meant to be limiting. Any reference to applying or providing a second marking material (or second mark) “over” or “on top of” (or other similar references) a first marking material (or first mark) is not meant to be limiting. Rather, it should be understood that the application of the first and second marking materials may be reversed, or concurrent, or even more than once. For example, it is within the scope of this disclosure that a second marking material may be applied to a substrate, followed by an application of a first marking material (the material for the security mark, and that is configured to react to non-visible light). Alternatively, it is understood that either or both of the first and second marking materials may be applied to a substrate more than once. Thus, the steps of method 200 as described herein are not limiting in their order.
Also, it should be understood that this disclosure also includes methods for applying more than one composite security element to a substrate, as well as a substrate comprising more than one composite security element. For example, in some embodiments, there may or may not be more than one predetermined area on a substrate for applying a first marking material and/or a second marking material. Furthermore, it should be understood any combination of the first and second pattern marks may be applied to, used with, and/or provided on a substrate. In an embodiment, it is envisioned that a composite security element (i.e., a combination of a first pattern mark in a first (active) marking material and a second pattern mark in a second (passive) marking material) may be applied or provided on a substrate in combination with one or more additional marks in a marking material on a substrate. For example, both a composite security element and an additional first pattern mark (or other security mark in a reactive or active marking material) may be provided on substrate. Any number of marking materials (active or passive) may be provided on the substrate in addition to the marking materials for the composite security element, as described herein.
Additionally, application of a first pattern mark in a first marking material to a substrate either alone or in combination with second marking material need not have a similar shape for each application. For example, in an embodiment where first marking material is used to apply more than one security mark to a substrate (with or without second marking material), each application may comprise a separate and distinct pattern or design. In an embodiment, an application of first marking material to first substrate may comprise a substantially distinct design as compared to a second substrate. Similarly, a second marking material may be applied in a substantially distinct design on a substrate.
Generally, any suitable printing apparatus may be employed to implement method 200 and to place the pattern marks on the substrate or paper. The marking materials of this disclosure can be used in or applied by an image processing apparatus configured to generate an ink-based or toner-based image on a substrate, followed by, or preceded by, or by consecutively applying the first (active) and second (passive) marking materials onto the substrate. For example, the printing apparatus may be a machine that incorporates a plurality of marking material applicators, stations, or housings, such that color marking materials (e.g., cyan, magenta, yellow, and black, or CMYK), the active marking material, and the passive marking material may be housed therein for application to the substrate. If a device comprises six toner developer stations, for example, two of the stations may be used for the disclosed marking materials (each being provided in a separate station) (e.g., see
In another embodiment, for example, the first and second marking materials may be used in place of one or more color marking material applicators in a printing apparatus. For example, a four-color ink machine may be configured such that two of the color cartridges are replaced (e.g., temporarily) by two cartridges carrying first and second marking materials (e.g., see
Of course, such exemplary printing devices are not meant to be limiting. For example, in yet another embodiment, the first and second marking materials are applied using a separate printing apparatus or device, which may be an auxiliary device that is part of the printing apparatus, or an external device (e.g., see
The herein described embodiments may be used in inkjet device, such as, for example, a solid inkjet printer, an aqueous inkjet printer, or a UV inkjet printer, or they may be used in an electrophotographic printing system or a lithographic printing system.
For explanatory purposes only,
For example, the apparatus 300 may comprise an image capture device 302, at least one processor 304, a controller(s) 306, memory 308 and/or storage 310, marking devices 312, and an output device 314. Each of the devices shown in system 300 may also be considered modules, and, therefore, the terms “device” and “module” are used interchangeably herein. Furthermore, the devices or modules illustrated in
Generally, some of devices or modules shown in
An output device 314 may be provided to output the image data (e.g., as noted in the method 700 at block 208). Output device 314 may be any type of device that is designed to output the image data. For example, the output device may be an MFD, printer, or copier, for example. In an embodiment, the output device 314 may decompress the image data and information in the background metadata before output. In some embodiments, a decompressor 316 is provided in output device 314 of system 300 to decompress image data before outputting the image data with output device 314, if needed. The decompressor 316 and output device 314 may be the same module, or separate modules.
The marking devices 312 are applicators, stations, print-heads, or housings incorporated into the output device 314 of the apparatus 300 used to mark or apply marking materials, such as color and security inks for printing image data of a document and a composite security element thereon. In an embodiment, controller 306 is used to control one or more marking devices or applicators 312 of system 300. The marking applicators for the first (active) and second (passive) marking materials may comprise the same marking applicator or different marking applicators. Any number of marking applicators 312 may be used. For example, as previously noted, the printing apparatus 300 may be a machine that houses both color marking materials (e.g., CMYK), the first (active) marking material, and the second (passive) marking for application using applicators 312.
In another embodiment, which is illustrated in
In an embodiment, the four-color ink apparatus 300 of
The processor 304, marking device(s) 312, and/or other associated modules of any of the apparatuses 300 illustrated in
In some embodiments, although not shown, any of the apparatuses 300 and/or printing device 318 may comprise a curing device(s) for curing the marking material(s). For example, the curing device may be a device included in or associated with any one of the output devices 314, 314A, and/or 314B, or printing device 318.
In an embodiment, the apparatuses, system and method described herein may also include use of a light emitting source, such as radiation source 150 shown in
In an embodiment, the apparatuses, system, and method also includes a machine or device that is used to distinguish or discern a security mark (the first pattern mark) when it is illuminated by non-visible light. In an embodiment, a machine (e.g., a scanner) may include a light source. In another embodiment, a machine (e.g., a camera) may be aided by a light source (e.g., laser or radiation source).
It should be understood that the security markings (i.e., first pattern marks) 110, 118, and 124 shown in
The marking materials for the first pattern mark and the second pattern mark as disclosed herein may comprise any number of materials including, but not limited to, inks or toners. For example, in an embodiment, the active marking material comprises a material from the group consisting of: fluorescent, luminescent, phosphorescent, or scintillating material, or a material that has absorption characteristics in the non-visible wavelengths which are significantly higher than that of the second marking material and/or substrate. In an embodiment, the marking material may comprise polymers or resins, and UV fluorescent component, for example. In an embodiment, materials and/or processes such as those described in U.S. Pat. No. 6,673,500, assigned to the same assignee, Xerox Corporation, and which is hereby incorporated by reference in its entirety, may be used as one or more of the herein disclosed marking materials for marking a composite security element.
Additionally, the qualities or features of the marking materials should not be limited. For example, it is within the scope of this disclosure that the first pattern mark and the second pattern mark are transparent. The first and second pattern marks may be transparent but not colorless, or both colorless and transparent, or in some applications, neither colorless nor transparent. In an embodiment, the color and transparency of the two pattern marks are substantially similar. For example, it may be desirable to utilize first and second marking materials with a tint or color that is transparent. Accordingly, it should be understood that a number of types and different marking materials may be used, so as the first and second pattern marks are indistinguishable from each other via at least a naked human eye in visible light. In an embodiment, for example, an existing marking material (for outputting an image on the substrate)—such as C, M, Y or K inks or toners—may be used as the passive marking material, in combination with another material, which is an active marking material. However, this example is not meant to be limiting.
While the principles of the disclosure have been made clear in the illustrative embodiments set forth above, it will be apparent to those skilled in the art that various modifications may be made to the structure, arrangement, proportion, elements, materials, and components used in the practice of the disclosure.
It will be appreciated that various of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems/devices or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims.